Needle probe guide

ABSTRACT

A device for guiding electrodes relative to a tissue treatment region. The device can comprise a body have a plurality of passages therethrough. Each passage can axially restrain an electrode positioned therein. When each electrode is axially restrained in a passage, the distal ends of the electrodes can be spaced a predetermined distance apart. Further, the electrodes can be held in a parallel or substantially parallel alignment when axially retained in the passages. The predetermined distance between the electrodes can correspond to a treatment distance in a tissue treatment region and the distal ends of the electrodes can be operably structured to conduct current therebetween when at least one of electrodes is energized by an energy source.

FIELD OF TECHNOLOGY

The present invention generally relates to surgical devices and methods.

BACKGROUND

Electrical ablation therapy has been employed in medicine for the treatment of undesirable tissue such as diseased tissue, cancer, malignant and benign tumors, masses, lesions, and other abnormal tissue growths. While conventional apparatuses, systems, and methods for the electrical ablation of undesirable tissue are effective, one drawback with conventional electrical ablation treatment is the resulting permanent damage that may occur to the healthy tissue surrounding the abnormal tissue due primarily to the detrimental thermal effects resulting from exposing the tissue to thermal energy generated by the electrical ablation device. This may be particularly true when exposing the tissue to electric potentials sufficient to cause cell necrosis using high temperature thermal therapies including focused ultrasound ablation, radiofrequency (RF) ablation, or interstitial laser coagulation. Other techniques for tissue ablation include chemical ablation, in which chemical agents are injected into the undesirable tissue to cause ablation as well as surgical excision, cryotherapy, radiation, photodynamic therapy, Moh's micrographic surgery, topical treatments with 5-fluorouracil, laser ablation. Other drawbacks of conventional thermal, chemical, and other ablation therapy are cost, length of recovery, and the extraordinary pain inflicted on the patient.

Conventional thermal, chemical, and other ablation techniques have been employed for the treatment of a variety of undesirable tissue. Thermal and chemical ablation techniques have been used for the treatment of varicose veins resulting from reflux disease of the greater saphenous vein (GSV), in which the varicose vein is stripped and then is exposed to either chemical or thermal ablation. Other techniques for the treatment of undesirable tissue are more radical. Prostate cancer, for example, may be removed using a prostatectomy, in which the entire or part of prostate gland and surrounding lymph nodes are surgically removed. Like most other forms of cancer, radiation therapy may be used in conjunction with or as an alternate method for the treatment of prostate cancer. Another thermal ablation technique for the treatment of prostate cancer is RF interstitial tumor ablation (RITA) via trans-rectal ultrasound guidance. While these conventional methods for the treatment of prostate cancer are effective, they are not preferred by many surgeons and may result in detrimental thermal effects to healthy tissue surrounding the prostate. Similar thermal ablation techniques may be used for the treatment of basal cell carcinoma (BCC) tissue, a slowly growing cutaneous malignancy derived from the rapidly proliferating basal layer of the epidermis. BCC tissue in tumors ranging in size from about 5 mm to about 40 mm may be thermally ablated with a pulsed carbon dioxide laser. Nevertheless, carbon dioxide laser ablation is a thermal treatment method and may cause permanent damage to healthy tissue surrounding the BCC tissue. Furthermore, this technique requires costly capital investment in carbon dioxide laser equipment.

Undesirable tissue growing inside a body lumen such as the esophagus, large bowel, or in cavities formed in solid tissue such as the breast, for example, can be difficult to destroy using conventional ablation techniques. Surgical removal of undesirable tissue, such as a malignant or benign tumor, from the breast is likely to leave a cavity. Surgical resection of residual intralumenal tissue may remove only a portion of the undesirable tissue cells within a certain margin of healthy tissue. Accordingly, some undesirable tissue is likely to remain within the wall of the cavity due to the limitation of conventional ablation instrument configurations, which may be effective for treating line-of-sight regions of tissue, but may be less effective for treating the residual undesirable tissue.

Accordingly, there remains a need for improved electrical ablation apparatuses, systems, and methods for the treatment of undesirable tissue found in diseased tissue, cancer, malignant and benign tumors, masses, lesions, and other abnormal tissue growths. There remains a need for minimally invasive treatment of undesirable tissue through the use of irreversible electroporation (IRE) ablation techniques without causing the detrimental thermal effects of conventional thermal ablation techniques.

SUMMARY

An aspect of the present disclosure is directed to a device for guiding electrodes relative to a tissue treatment region. The device comprises a body comprising a first passage through the body, wherein the first passage is structured to axially restrain a first electrode, and wherein the first electrode comprises a proximal end and a distal end. The body also comprises a second passage through the body, wherein the second passage is substantially parallel to the first passage, wherein the second passage is structured to axially restrain a second electrode, and wherein the second electrode comprises a proximal end and a distal end. Further, the distal end of the first electrode is spaced a predetermined distance from the distal end of the second electrode when the first electrode is restrained in the first passage and the second electrode is restrained in the second passage. The predetermined distance corresponds to a treatment distance in the tissue treatment region. Additionally, the distal ends of the first and second electrodes are operably structured to conduct current.

FIGURES

The novel features of the various described embodiments are set forth with particularity in the appended claims. The various embodiments, however, both as to organization and methods of operation, together with advantages thereof, may be understood in accordance with the following description taken in conjunction with the accompanying drawings as follows.

FIG. 1 is a schematic of an electrical ablation system and a flexible endoscope according to various embodiments of the present disclosure;

FIGS. 2A-D depict one embodiment of the electrical ablation device of the electrical ablation system of FIG. 1 in various phases of deployment;

FIG. 3 is a perspective view of one embodiment of an electrical ablation device comprising multiple electrode probes according to various embodiments of the present disclosure;

FIG. 4 is a schematic illustrating the electrical ablation system shown in FIGS. 1 and 2A-D in use to treat undesirable tissue located in the liver according to various embodiments of the present disclosure;

FIG. 5 is a detailed schematic illustrating the electrical ablation system shown in FIG. 4 in use to treat undesirable tissue located in the liver according to various embodiments of the present disclosure;

FIG. 6 is a perspective view of a probe guide according to various embodiments of the present disclosure;

FIG. 7 is an elevational view of one embodiment of the probe guide of FIG. 6;

FIG. 8 is an elevational, cross-sectional view of one embodiment of the probe guide of FIG. 6;

FIG. 9 is a perspective view of a probe guide having a handle according to various embodiments of the present disclosure;

FIG. 10 is an elevational view of one embodiment of the probe guide of FIG. 9;

FIG. 11 is a perspective view of a probe guide according to various embodiments of the present disclosure;

FIG. 12 is a perspective view of a probe guide having a base according to various embodiments of the present disclosure;

FIG. 13 is an elevational view of one embodiment of the probe guide of FIG. 12;

FIG. 14 is a plan view of one embodiment of the probe guide of FIG. 12;

FIG. 15 is a perspective view of a probe guide according to various embodiments of the present disclosure;

FIG. 16 is a perspective view of a probe guide having a base according to various embodiments of the present disclosure;

FIG. 17 is a perspective view of a probe guide having orthogonal outlets according to various embodiments of the present disclosure;

FIG. 18 is a perspective view of a probe guide having an outlet according to various embodiments of the present disclosure;

FIG. 19 is a plan view of a probe guide having indicia of measurement according to various embodiments of the present disclosure;

FIG. 20 is a perspective view of a probe guide comprising a bore, and a plurality of ribs and vents according to various embodiments of the present disclosure;

FIG. 21 is a plan view of one embodiment of the probe guide of FIG. 20;

FIG. 22 is a perspective, exploded view of a probe guide having a removable handle according to various embodiments of the present disclosure;

FIG. 23 is an elevational view of the removeable handle of one embodiment of the probe guide of FIG. 22;

FIG. 24 is a perspective view of a locking element of one embodiment of the probe guide of FIG. 22;

FIG. 25 is a perspective view of the body portion of one embodiment of the probe guide of FIG. 22;

FIG. 26 is an elevational view of the body portion of one embodiment of the probe guide of FIG. 22;

FIG. 27 is a plan view of the body portion of one embodiment of the probe guide of FIG. 22;

FIG. 28 is a perspective view of a spring loaded probe guide according to various embodiments of the present disclosure;

FIG. 29 is an elevational view of one embodiment of the spring loaded probe guide of FIG. 28;

FIG. 30 is a perspective view of the first body portion of one embodiment of the spring loaded probe guide of FIG. 28;

FIG. 31 is a perspective view of the second body portion and the fasteners of one embodiment of the spring loaded probe guide of FIG. 28;

FIG. 32 is a perspective view of a fastener of one embodiment of the spring loaded probe guide of FIG. 28;

FIG. 33 is a perspective view of one embodiment of the spring loaded probe guide of FIG. 28 with the first body portion removed therefrom;

FIG. 34 is an elevational view of one embodiment of the spring loaded probe guide of FIG. 28 with the first body portion removed therefrom;

FIG. 35 is a perspective view of a spring loaded probe guide having a leaf spring and with the second body portion removed therefrom according to various embodiments of the present disclosure;

FIG. 36 is an elevational view of one embodiment of the spring loaded probe guide of FIG. 35 with the first body portion removed therefrom;

FIG. 37 is a perspective view of a spring loaded probe guide according to various embodiments of the present disclosure;

FIG. 38 is a perspective view of the second body portion of one embodiment of the spring loaded probe guide of FIG. 37;

FIG. 39 is an elevational view of the second body portion of one embodiment of the spring loaded probe guide of FIG. 37;

FIG. 40 is a perspective view of a spring loaded probe guide according to various embodiments of the present disclosure;

FIG. 41 is a perspective view of the first body portion of one embodiment of the spring loaded probe guide of FIG. 40;

FIG. 42 is an elevational view of the first body portion of one embodiment of the spring loaded probe guide of FIG. 40;

FIG. 43 is a plan view of the first body portion of one embodiment of the spring loaded probe guide of FIG. 40;

FIG. 44 is a perspective view of the second body portion of one embodiment of the spring loaded probe guide of FIG. 40;

FIG. 45 is an elevational view of a probe guide according to various embodiments of the present disclosure;

FIG. 46 is an elevational view of one embodiment of the probe guide of FIG. 45;

FIG. 47 is a plan view of one embodiment of the probe guide of FIG. 45;

FIG. 48 is a perspective view an elastomeric probe guide showing the outline of the elastomeric probe guide in an initial, undeformed configuration and in a second, deformed configuration according to various embodiments of the present disclosure;

FIG. 49 is a perspective view of one embodiment of the elastomeric probe guide of FIG. 48 depicting the body portion in the initial, undeformed configuration;

FIG. 50 is a perspective view of one embodiment of the elastomeric probe guide of FIG. 48 depicting the body portion in the second, deformed configuration;

FIG. 51 is an elevational, cross-sectional view of one embodiment of the elastomeric probe guide of FIG. 48 depicting the body portion in an initial, undeformed configuration;

FIG. 52 is a plan view of a frame for molding the elastomeric probe guide of FIG. 48 according to various embodiments of the present disclosure;

FIG. 53 is an elevational view of an elastomeric probe guide depicting the probe guide in an initial, undeformed configuration according to various embodiments of the present disclosure;

FIG. 54 is an elevational view of one embodiment of the elastomeric probe guide of FIG. 43 depicting the probe guide in a deformed configuration;

FIG. 55 is an elevational view of a probe guide having an elastomeric body and a substantially rigid beam according to various embodiments of the present disclosure; and

FIG. 56 is a perspective view of a probe guide according to various embodiments of the present disclosure.

DESCRIPTION

Various embodiments are directed to apparatuses, systems, and methods for the electrical ablation treatment of undesirable tissue such as diseased tissue, cancer, malignant and benign tumors, masses, lesions, and other abnormal tissue growths. Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and illustrated in the accompanying drawings. It will be understood, however, that the embodiments may be practiced without such specific details. In other instances, well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. Those of ordinary skill in the art will understand that the embodiments described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and do not necessarily limit the scope of the embodiments, the scope of which is defined solely by the appended claims.

Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment”, or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment,” or “in an embodiment”, or the like, in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment may be combined, in whole or in part, with the features structures, or characteristics of one or more other embodiments without limitation.

It will be appreciated that the terms “operator”, “surgeon” and “clinician” may be used interchangeably throughout the specification with reference to a person, multiple persons, a robotic device, multiple robotic devices, or a combination thereof that may use a surgical instrument described herein and/or perform a step of a method described herein. These terms are not intended to be limiting and absolute.

It will be appreciated that the terms “proximal” and “distal” may be used throughout the specification with reference to a clinician manipulating one end of an instrument used to treat a patient. The term “proximal” refers to the portion of the instrument closest to the clinician and the term “distal” refers to the portion located furthest from the clinician. It will be further appreciated that for conciseness and clarity, spatial terms such as “vertical,” “horizontal,” “up,” and “down” may be used herein with respect to the illustrated embodiments. However, surgical instruments may be used in many orientations and positions, and these terms are not intended to be limiting and absolute.

Electrical ablation devices in accordance with the described embodiments may comprise one or more electrodes configured to be positioned into or proximal to undesirable tissue in a tissue treatment region (e.g., target site, worksite) where there is evidence of abnormal tissue growth, for example. In general, the electrodes comprise an electrically conductive portion (e.g., medical grade stainless steel) and are configured to electrically couple to an energy source. Once the electrodes are positioned into or proximal to the undesirable tissue, an energizing potential is applied to the electrodes to create an electric field to which the undesirable tissue is exposed. The energizing potential (and the resulting electric field) may be characterized by multiple parameters such as frequency, amplitude, pulse width (duration of a pulse or pulse length), and/or polarity. Depending on the diagnostic or therapeutic treatment to be rendered, a particular electrode may be configured either as an anode (+) or a cathode (−) or may comprise a plurality of electrodes with at least one configured as an anode and at least one other configured as a cathode. Regardless of the initial polar configuration, the polarity of the electrodes may be reversed by reversing the polarity of the output of the energy source.

In various embodiments, a suitable energy source may comprise an electrical waveform generator, which may be configured to create an electric field that is suitable to create irreversible electroporation in undesirable tissue at various electric field amplitudes and durations. The energy source may be configured to deliver irreversible electroporation pulses in the form of direct-current (DC) and/or alternating-current (AC) voltage potentials (e.g., time-varying voltage potentials) to the electrodes. The irreversible electroporation pulses may be characterized by various parameters such as frequency, amplitude, pulse length, and/or polarity. The undesirable tissue may be ablated by exposure to the electric potential difference across the electrodes.

In one embodiment, the energy source may comprise a wireless transmitter to deliver energy to the electrodes using wireless energy transfer techniques via one or more remotely positioned antennas. Wireless energy transfer or wireless power transmission is the process of transmitting electrical energy from an energy source to an electrical load without interconnecting wires. An electrical transformer is the simplest instance of wireless energy transfer. The primary and secondary circuits of a transformer are not directly connected and the transfer of energy takes place by electromagnetic coupling through a process known as mutual induction. Power also may be transferred wirelessly using RF energy. Wireless power transfer technology using RF energy is produced by Powercast, Inc. and can achieve an output of 6 volts for a little over one meter. Other low-power wireless power technology has been proposed such as described in U.S. Pat. No. 6,967,462, the entire disclosure of which is incorporated by reference herein.

The apparatuses, systems, and methods in accordance with certain described embodiments may be configured for minimally invasive ablation treatment of undesirable tissue through the use of irreversible electroporation to be able to ablate undesirable tissue in a controlled and focused manner without inducing thermally damaging effects to the surrounding healthy tissue. The apparatuses, systems, and methods in accordance with the described embodiments may be configured to ablate undesirable tissue through the use of electroporation or electropermeabilization. More specifically, in various embodiments, the apparatuses, systems, and methods in accordance with the described embodiments may be configured to ablate undesirable tissue through the use of irreversible electroporation. Electroporation increases the permeabilization of a cell membrane by exposing the cell to electric pulses. The external electric field (electric potential/per unit length) to which the cell membrane is exposed to significantly increases the electrical conductivity and permeability of the plasma in the cell membrane. The primary parameter affecting the transmembrane potential is the potential difference across the cell membrane. Irreversible electroporation is the application of an electric field of a specific magnitude and duration to a cell membrane such that the permeabilization of the cell membrane cannot be reversed, leading to cell death without inducing a significant amount of heat in the cell membrane. The destabilizing potential forms pores in the cell membrane when the potential across the cell membrane exceeds its dielectric strength causing the cell to die under a process known as apoptosis and/or necrosis. The application of irreversible electroporation pulses to cells is an effective way to ablate large volumes of undesirable tissue without deleterious thermal effects to the surrounding healthy tissue associated with thermal-inducing ablation treatments. This is because irreversible electroporation destroys cells without heat and thus does not destroy the cellular support structure or regional vasculature. A destabilizing irreversible electroporation pulse, suitable to cause cell death without inducing a significant amount of thermal damage to the surrounding healthy tissue, may have amplitude in the range of about several hundred to about several thousand volts and is generally applied across biological membranes over a distance of about several millimeters, for example, for a relatively long duration. Thus, the undesirable tissue may be ablated in-vivo through the delivery of destabilizing electric fields by quickly creating cell necrosis.

The apparatuses, systems, and methods for electrical ablation therapy in accordance with the described embodiments may be adapted for use in minimally invasive surgical procedures to access the tissue treatment region in various anatomic locations such as the brain, lungs, breast, liver, gall bladder, pancreas, prostate gland, and various internal body lumen defined by the esophagus, stomach, intestine, colon, arteries, veins, anus, vagina, cervix, fallopian tubes, and the peritoneal cavity, for example, without limitation. Minimally invasive electrical ablation devices may be introduced to the tissue treatment region using a trocar inserted though a small opening formed in the patient's body or through a natural body orifice such as the mouth, anus, or vagina using translumenal access techniques known as Natural Orifice Translumenal Endoscopic Surgery (NOTES)™. Once the electrical ablation devices (e.g., electrodes) are located into or proximal to the undesirable tissue in the treatment region, electric field potentials can be applied to the undesirable tissue by the energy source. The electrical ablation devices can comprise portions that may be inserted into the tissue treatment region percutaneously (e.g., where access to inner organs or other tissue is done via needle-puncture of the skin). Other portions of the electrical ablation devices may be introduced into the tissue treatment region endoscopically (e.g., laparoscopically and/or thoracoscopically) through trocars or working channels of the endoscope, through small incisions, or transcutaneously (e.g., where electric pulses are delivered to the tissue treatment region through the skin).

FIG. 1 illustrates one embodiment of an electrical ablation system 10. The electrical ablation system 10 may be employed to ablate undesirable tissue such as diseased tissues, cancers, tumors, masses, lesions, abnormal tissue growths inside a patient using electrical energy. The electrical ablation system 10 may be used in conjunction with endoscopic, laparoscopic, thoracoscopic, open surgical procedures via small incisions or keyholes, percutaneous techniques, transcutaneous techniques, and/or external non-invasive techniques, or any combinations thereof without limitation. The electrical ablation system 10 may be configured to be positioned within a natural body orifice of the patient such as the mouth, anus, or vagina and advanced through internal body lumen or cavities such as the esophagus, colon, cervix, urethra, for example, to reach the tissue treatment region. The electrical ablation system 10 also may be configured to be positioned and passed through a small incision or keyhole formed through the skin or abdominal wall of the patient to reach the tissue treatment region using a trocar. The tissue treatment region may be located in the brain, lungs, breast, liver, gall bladder, pancreas, prostate gland, various internal body lumen defined by the esophagus, stomach, intestine, colon, arteries, veins, anus, vagina, cervix, fallopian tubes, and the peritoneal cavity, for example, without limitation. The electrical ablation system 10 can be configured to treat a number of lesions and ostepathologies comprising metastatic lesions, tumors, fractures, infected sites, and/or inflamed sites. Once positioned into or proximate the tissue treatment region, the electrical ablation system 10 can be actuated (e.g., energized) to ablate the undesirable tissue. In one embodiment, the electrical ablation system 10 may be configured to treat diseased tissue in the gastrointestinal (GI) tract, esophagus, lung, or stomach that may be accessed orally. In another embodiment, the electrical ablation system 10 may be adapted to treat undesirable tissue in the liver or other organs that may be accessible using translumenal access techniques such as, without limitation, NOTES™ techniques, where the electrical ablation devices may be initially introduced through a natural orifice such as the mouth, anus, or vagina and then advanced to the tissue treatment site by puncturing the walls of internal body lumen such as the stomach, intestines, colon, cervix. In various embodiments, the electrical ablation system 10 may be adapted to treat undesirable tissue in the brain, liver, breast, gall bladder, pancreas, or prostate gland, using one or more electrodes positioned percutaneously, transcutaneously, translumenally, minimally invasively, and/or through open surgical techniques, or any combination thereof.

In one embodiment, the electrical ablation system 10 may be employed in conjunction with a flexible endoscope 12, as well as a rigid endoscope, laparoscope, or thoracoscope, such as the GIF-H180 model available from Olympus Corporation. In one embodiment, the endoscope 12 may be introduced to the tissue treatment region trans-anally through the colon, trans-orally through the esophagus and stomach, trans-vaginally through the cervix, transcutaneously, or via an external incision or keyhole formed in the abdomen in conjunction with a trocar. The electrical ablation system 10 may be inserted and guided into or proximate the tissue treatment region using the endoscope 12.

In the embodiment illustrated in FIG. 1, the endoscope 12 comprises an endoscope handle 34 and an elongate relatively flexible shaft 32. The distal end of the flexible shaft 32 may comprise a light source and a viewing port. Optionally, the flexible shaft 32 may define one or more working channels for receiving various instruments, such as electrical ablation devices, for example, therethrough. Images within the field of view of the viewing port are received by an optical device, such as a camera comprising a charge coupled device (CCD) usually located within the endoscope 12, and are transmitted to a display monitor (not shown) outside the patient.

In one embodiment, the electrical ablation system 10 may comprise an electrical ablation device 20, a plurality of electrical conductors 18, a handpiece 16 comprising an activation switch 62, and an energy source 14, such as an electrical waveform generator, electrically coupled to the activation switch 62 and the electrical ablation device 20. The electrical ablation device 20 comprises a relatively flexible member or shaft 22 that may be introduced to the tissue treatment region using a variety of known techniques such as an open incision and a trocar, through one of more of the working channels of the endoscope 12, percutaneously, or transcutaneously, for example.

In one embodiment, one or more electrodes (e.g., needle electrodes, balloon electrodes), such as first and second electrodes 24 a, 24 b, extend out from the distal end of the electrical ablation device 20. In one embodiment, the first electrode 24 a may be configured as the positive electrode and the second electrode 24 b may be configured as the negative electrode. The first electrode 24 a is electrically connected to a first electrical conductor 18 a, or similar electrically conductive lead or wire, which is coupled to the positive terminal of the energy source 14 through the activation switch 62. The second electrode 24 b is electrically connected to a second electrical conductor 18 b, or similar electrically conductive lead or wire, which is coupled to the negative terminal of the energy source 14 through the activation switch 62. The electrical conductors 18 a, 18 b are electrically insulated from each other and surrounding structures, except for the electrical connections to the respective electrodes 24 a, 24 b. In various embodiments, the electrical ablation device 20 may be configured to be introduced into or proximate the tissue treatment region using the endoscope 12 (laparoscope or thoracoscope), open surgical procedures, or external and non-invasive medical procedures. The electrodes 24 a, 24 b may be referred to herein as endoscopic or laparoscopic electrodes, although variations thereof may be inserted transcutaneously or percutaneously. As described herein, either one or both electrodes 24 a, 24 b may be adapted and configured to slideably move in and out of a cannula, lumen, or channel defined within the flexible shaft 22.

Once the electrodes 24 a, 24 b are positioned at the desired location into or proximate the tissue treatment region, the electrodes 24 a, 24 b may be connected to or disconnected from the energy source 14 by actuating or de-actuating the switch 62 on the handpiece 16. The switch 62 may be operated manually or may be mounted on a foot switch (not shown), for example. The electrodes 24 a, 24 b deliver electric field pulses to the undesirable tissue. The electric field pulses may be characterized based on various parameters such as pulse shape, amplitude, frequency, and duration. The electric field pulses may be sufficient to induce irreversible electroporation in the undesirable tissue. The induced potential depends on a variety of conditions such as tissue type, cell size, and electrical pulse parameters. The primary electrical pulse parameter affecting the transmembrane potential for a specific tissue type is the amplitude of the electric field and pulse length that the tissue is exposed to.

In one embodiment, a protective sleeve or sheath 26 may be slideably disposed over the flexible shaft 22 and within a handle 28. In another embodiment, the sheath 26 may be slideably disposed within the flexible shaft 22 and the handle 28, without limitation. The sheath 26 is slideable and may be located over the electrodes 24 a, 24 b to protect the trocar and prevent accidental piercing when the electrical ablation device 20 is advanced therethrough. Either one or both of the electrodes 24 a, 24 b of the electrical ablation device 20 may be adapted and configured to slideably move in and out of a cannula, lumen, or channel formed within the flexible shaft 22. As described herein, the second electrode 24 b may be fixed in place. The second electrode 24 b may provide a pivot about which the first electrode 24 a can be moved in an arc to other points in the tissue treatment region to treat larger portions of the diseased tissue that cannot be treated by fixing the electrodes 24 a, 24 b in one location. In one embodiment, either one or both of the electrodes 24 a, 24 b may be adapted and configured to slideably move in and out of a working channel formed within a flexible shaft 32 of the flexible endoscope 12 or may be located independently of the flexible endoscope 12. Various features of the first and second electrodes 24 a, 24 b are described in more detail in FIGS. 2A-D.

In one embodiment, the first and second electrical conductors 18 a, 18 b may be provided through the handle 28. In the illustrated embodiment, the first electrode 24 a can be slideably moved in and out of the distal end of the flexible shaft 22 using a slide member 30 to retract and/or advance the first electrode 24 a. In various embodiments either or both electrodes 24 a, 24 b may be coupled to the slide member 30, or additional slide members, to advance and retract the electrodes 24 a, 24 b, e.g., position the electrodes 24 a, 24 b. In the illustrated embodiment, the first electrical conductor 18 a coupled to the first electrode 24 a is coupled to the slide member 30. In this manner, the first electrode 24 a, which is slideably movable within the cannula, lumen, or channel defined by the flexible shaft 22, can advanced and retracted with the slide member 30.

In various other embodiments, transducers or sensors 29 may be located in the handle 28 of the electrical ablation device 20 to sense the force with which the electrodes 24 a, 24 b penetrate the tissue in the tissue treatment zone. This feedback information may be useful to determine whether either one or both of the electrodes 24 a, 24 b have been properly inserted in the tissue treatment region. As is particularly well known, cancerous tumor tissue tends to be denser than healthy tissue and thus greater force is required to insert the electrodes 24 a, 24 b therein. The transducers or sensors 29 can provide feedback to the operator, surgeon, or clinician to physically sense when the electrodes 24 a, 24 b are placed within the cancerous tumor. The feedback information provided by the transducers or sensors 29 may be processed and displayed by circuits located either internally or externally to the energy source 14. The sensor 29 readings may be employed to determine whether the electrodes 24 a, 24 b have been properly located within the cancerous tumor thereby assuring that a suitable margin of error has been achieved in locating the electrodes 24 a, 24 b.

In one embodiment, the input to the energy source 14 may be connected to a commercial power supply by way of a plug (not shown). The output of the energy source 14 is coupled to the electrodes 24 a, 24 b, which may be energized using the activation switch 62 on the handpiece 16, or in one embodiment, an activation switch mounted on a foot activated pedal (not shown). The energy source 14 may be configured to produce electrical energy suitable for electrical ablation, as described in more detail herein.

In one embodiment, the electrodes 24 a, 24 b are adapted and configured to electrically couple to the energy source 14 (e.g., generator, waveform generator). Once electrical energy is coupled to the electrodes 24 a, 24 b, an electric field is formed at a distal end of the electrodes 24 a, 24 b. The energy source 14 may be configured to generate electric pulses at a predetermined frequency, amplitude, pulse length, and/or polarity that are suitable to induce irreversible electroporation to ablate substantial volumes of undesirable tissue in the treatment region. For example, the energy source 14 may be configured to deliver DC electric pulses having a predetermined frequency, amplitude, pulse length, and/or polarity suitable to induce irreversible electroporation to ablate substantial volumes of undesirable tissue in the treatment region. The DC pulses may be positive or negative relative to a particular reference polarity. The polarity of the DC pulses may be reversed or inverted from positive-to-negative or negative-to-positive a predetermined number of times to induce irreversible electroporation to ablate substantial volumes of undesirable tissue in the treatment region.

In one embodiment, a timing circuit may be coupled to the output of the energy source 14 to generate electric pulses. The timing circuit may comprise one or more suitable switching elements to produce the electric pulses. For example, the energy source 14 may produce a series of n electric pulses (where n is any positive integer) of sufficient amplitude and duration to induce irreversible electroporation suitable for tissue ablation when the n electric pulses are applied to the electrodes 24 a, 24 b. In one embodiment, the electric pulses may have a fixed or variable pulse length, amplitude, and/or frequency.

The electrical ablation device 20 may be operated either in bipolar or monopolar mode. In bipolar mode, the first electrode 24 a is electrically connected to a first polarity and the second electrode 24 b is electrically connected to the opposite polarity. For example, in monopolar mode, the first electrode 24 a is coupled to a prescribed voltage and the second electrode 24 b is set to ground. In the illustrated embodiment, the energy source 14 may be configured to operate in either the bipolar or monopolar modes with the electrical ablation system 10. In bipolar mode, the first electrode 24 a is electrically connected to a prescribed voltage of one polarity and the second electrode 24 b is electrically connected to a prescribed voltage of the opposite polarity. When more than two electrodes are used, the polarity of the electrodes may be alternated so that any two adjacent electrodes may have either the same or opposite polarities, for example.

In one embodiment, the energy source 14 may be configured to produce RF waveforms at predetermined frequencies, amplitudes, pulse widths or durations, and/or polarities suitable for electrical ablation of cells in the tissue treatment region. One example of a suitable RF energy source is a commercially available conventional, bipolar/monopolar electrosurgical RF generator such as Model Number ICC 350, available from Erbe, GmbH.

In one embodiment, the energy source 14 may be configured to produce destabilizing electrical potentials (e.g., fields) suitable to induce irreversible electroporation. The destabilizing electrical potentials may be in the form of bipolar/monopolar DC electric pulses suitable for inducing irreversible electroporation to ablate tissue undesirable tissue with the electrical ablation device 20. A commercially available energy source suitable for generating irreversible electroporation electric field pulses in bipolar or monopolar mode is a pulsed DC generator such as Model Number ECM 830, available from BTX Molecular Delivery Systems. In bipolar mode, the first electrode 24 a may be electrically coupled to a first polarity and the second electrode 24 b may be electrically coupled to a second (e.g., opposite) polarity of the energy source 14. Bipolar/monopolar DC electric pulses may be produced at a variety of frequencies, amplitudes, pulse lengths, and/or polarities. Unlike RF ablation systems, however, which require high power and energy levels delivered into the tissue to heat and thermally destroy the tissue, irreversible electroporation requires very little energy input into the tissue to kill the undesirable tissue without the detrimental thermal effects because with irreversible electroporation the cells are destroyed by electric field potentials rather than heat.

In one embodiment, the energy source 14 may be coupled to the first and second electrodes 24 a, 24 b by either a wired or a wireless connection. In a wired connection, the energy source 14 is coupled to the electrodes 24 a, 24 b by way of the electrical conductors 18 a, 18 b, as shown. In a wireless connection, the electrical conductors 18 a, 18 b may be replaced with a first antenna (not shown) coupled the energy source 14 and a second antenna (not shown) coupled to the electrodes 24 a, 24 b, wherein the second antenna is remotely located from the first antenna. In one embodiment, the energy source may comprise a wireless transmitter to deliver energy to the electrodes using wireless energy transfer techniques via one or more remotely positioned antennas.

In at least one embodiment, the energy source 14 can be configured to produce DC electric pulses at frequencies in the range of approximately 1 Hz to approximately 10000 Hz, amplitudes in the range of approximately ±100 to approximately ±8000 VDC, and pulse lengths (e.g., pulse width, pulse duration) in the range of approximately 1 μs to approximately 100 ms. In at least one embodiment, the energy source can be configured to produce biphasic waveforms and/or monophasic waveforms that alternate around approximately 0V. In various embodiments, for example, the polarity of the electric potentials coupled to the electrodes 24 a, 24 b can be reversed during the electrical ablation therapy. For example, initially, the DC electric pulses can have a positive polarity and an amplitude in the range of approximately +100 to approximately +3000 VDC. Subsequently, the polarity of the DC electric pulses can be reversed such that the amplitude is in the range of approximately −100 to approximately −3000 VDC. In another embodiment, the DC electric pulses can have an initial positive polarity and amplitude in the range of approximately +100 to +6000 VDC and a subsequently reversed polarity and amplitude in the range of approximately −100 to approximately −6000 VDC.

In at least one embodiment, the undesirable cells in the tissue treatment region can be electrically ablated with DC pulses suitable to induce irreversible electroporation at frequencies of approximately 10 Hz to approximately 100 Hz, amplitudes in the range of approximately +700 to approximately +1500 VDC, and pulse lengths of approximately 10 μs to approximately 50 μs. In another embodiment, the abnormal cells in the tissue treatment region can be electrically ablated with an electrical waveform having an amplitude of approximately +500 VDC and pulse duration of approximately 20 ms delivered at a pulse period T or repetition rate, frequency f=1/T, of approximately 10 Hz. In another embodiment, the undesirable cells in the tissue treatment region can be electrically ablated with DC pulses suitable to induce irreversible electroporation at frequencies of approximately 200 Hz, amplitudes in the range of approximately +3000 VDC, and pulse lengths of approximately 10 ms. It has been determined that an electric field strength of 1,000V/cm can be suitable for destroying living tissue by inducing irreversible electroporation by DC electric pulses.

In various embodiments, the energy source 14 can be configured to produce AC electric pulses at frequencies in the range of approximately 1 Hz to approximately 10000 Hz, amplitudes in the range of approximately ±8000 to approximately ±8000 VAC, and pulse lengths (e.g., pulse width, pulse duration) in the range of approximately 1 μs to approximately 100 ms. In one embodiment, the undesirable cells in the tissue treatment region can be electrically ablated with AC pulses suitable to induce irreversible electroporation at pulse frequencies of approximately 4 Hz, amplitudes of approximately ±6000 VAC, and pulse lengths of approximately 20 ms. It has been determined that an electric field strength of 1,500V/cm can be suitable for destroying living tissue by inducing irreversible electroporation by AC electric pulses.

FIGS. 2A-D illustrate one embodiment of the electrical ablation device 20 in various phases of deployment. In the embodiment illustrated in FIGS. 2A-D, the sheath 26 is disposed over the flexible shaft 22, however, the sheath 26 may be disposed within the flexible shaft 22. The electrical ablation device 20 may be used in conjunction with the electrical ablation system 10 shown in FIG. 1. It will be appreciated that other devices and electrode configurations may be employed without limitation, such as, for example, the electrical ablation device 800 having electrodes 824 a, 824 b, 824 c, 824 d, as described herein. FIG. 2A illustrates an initial phase of deployment wherein the sheath 26 is extended in the direction indicated by arrow 40 to cover the electrodes 24 a, 24 b. The electrodes 24 a, 24 b may have dimensions of about 0.5 mm, about 1 mm, or about 1.5 mm in diameter. It will be appreciated that the dimensions of the electrodes 24 a, 24 b may be anywhere from about 0.5 mm to about 1.5 mm in diameter. The electrical ablation device 20 may be introduced into the tissue treatment region through a trocar, as illustrated in FIG. 4, for example. FIG. 2B illustrates another phase of deployment wherein the sheath 26 is retracted within the handle 28 in the direction indicated by arrow 42. In this phase of deployment, the first and second electrodes 24 a, 24 b extend through the distal end of the flexible shaft 22 and are ready to be inserted into or proximate the tissue treatment region. The first electrode 24 a may be retracted in direction 42 through a lumen 44 formed in the flexible shaft 22 by holding the handle 28 and pulling on the slide member 30. FIG. 2C illustrates a transition phase wherein the first electrode 24 a is the process of being retracted in direction 42 by pulling on the slide member 30 handle, for example, in the same direction. FIG. 2D illustrates another phase of deployment wherein the first electrode 24 a is in a fully retracted position. In this phase of deployment the electrical ablation device 20 can be pivotally rotated about an axis 46 defined by the second electrode 24 b. The electrodes 24 a, 24 b are spaced apart by a treatment distance “r.” The treatment distance “r” between the electrodes 24 a, 24 b may be 5.0 mm, about 7.5 mm, or about 10 mm. The treatment distance “r” between the electrodes 24 a, 24 b may be 1.0 cm, about 1.5 cm, or about 2 cm. Thus, the electrical ablation device 20 may be rotated in an arc about the pivot formed by the second electrode 24 b, the first electrode 24 a may be placed in a new location in the tissue treatment region within the treatment radius “r.” Retracting the first electrode 24 a and pivoting about the second electrode 24 b enables the surgeon or clinician to target and treat a larger tissue treatment region essentially comprising a circular region having a treatment radius “r,” which is the distance between the electrodes 24 a, 24 b. Thus, the electrodes 24 a, 24 b may be located in a plurality of positions in and around the tissue treatment region in order to treat much larger regions of tissue. Increasing the electrode 24 a, 24 b diameter and spacing the electrodes 24 a, 24 b further apart enables the generation of an electric field over a much larger tissue regions and thus the ablation of larger volumes of undesirable tissue. In this manner, the operator can treat a larger tissue treatment region comprising cancerous lesions, polyps, or tumors, for example.

Although the electrical ablation electrodes according to the described embodiments have been described in terms of the particular needle type electrodes 24 a, 24 b as shown in the embodiments illustrated in FIGS. 1 and 2A-D, other configurations of electrical ablation electrodes may be employed for the ablation of undesirable tissue, without limitation. In one embodiment, the electrical ablation device 20 may comprise two or more fixed electrodes that are non-retractable. In another embodiment, the electrical ablation device 20 may comprise two or more retractable electrodes, one embodiment of which is described below with reference to FIG. 3. In another embodiment, the electrical ablation device 20 may comprise at least one slidable electrode disposed within at least one working channel of the flexible shaft 32 of the endoscope 12. In another embodiment, the electrical ablation device 20 may comprise at least one electrode may be configured to be inserted into the tissue treatment region transcutaneously or percutaneously. Still in various other embodiments, the electrical ablation device 20 may comprise at least one electrode configured to be introduced to the tissue treatment region transcutaneously or percutaneously and at least one other electrode may be configured to be introduced to the tissue treatment region through at least one working channel of the flexible shaft 32 of the endoscope 12. The embodiments, however, are not limited in this context.

Various electrical ablation devices are disclosed in commonly-owned U.S. patent application Ser. No. 11/897,676 titled “ELECTRICAL ABLATION SURGICAL INSTRUMENTS,” filed Aug. 31, 2007, now U.S. Patent Application Publication No. 2009/0062788, the entire disclosure of which is incorporated herein by reference in its entirety. Various other devices are disclosed in commonly-owned U.S. patent application Ser. No. 12/352,375, titled “ELECTRICAL ABLATION DEVICES”, filed on Jan. 12, 2009, now U.S. Patent Application Publication No. 2010/0179530, the entire disclosure of which is incorporated herein by reference in its entirety.

As previously described with reference to the embodiments illustrated in FIGS. 2A-D, as shown in FIG. 3, in one embodiment, the protective sleeve or sheath 26 may be slidably disposed over the flexible shaft 22 and within the handle 28. In an initial phase of deployment, the sheath 26 is extended in direction 40 to cover the electrodes 824 a, 824 b, 824 c, 824 d to protect the trocar and prevent accidental piercing when the electrical ablation device 800 is advanced therethrough. Once the electrodes 824 a, 824 b, 824 c, 824 d are located into or proximate the tissue treatment region, the sheath 26 is retracted in direction 42 to expose the electrodes 824 a, 824 b, 824 c, 824 d. One or more of the electrodes 824 a, 824 b, 824 c, 824 d of the electrical ablation device 800 may be adapted and configured to slideably move in and out of a cannula, lumen, or channel formed within the flexible shaft 22. In one embodiment all of the electrodes 824 a, 824 b, 824 c, 824 d are configured to slideably move in and out channels formed within lumens formed within the flexible shaft 22, referred to for example as the lumen 44 in the embodiments illustrated in FIGS. 2A-D, to advance and retract the electrodes 824 a, 824 b, 824 c, 824 d as may be desired by the operator. Nevertheless, in other embodiments, it may be desired to fix all or certain ones of the one or more electrodes 824 a, 824 b, 824 c, 824 d in place.

The various embodiments of electrodes described in the present specification, e.g., the electrodes 24 a, 24 b, or 824 a-m, may be configured for use with an electrical ablation device (not shown) comprising an elongated flexible shaft to house the needle electrodes 24 a, 24 b, or 824 a-m, for example. The needle electrodes 24 a, 24 b, or 824 a-m, are free to extend past a distal end of the electrical ablation device. The flexible shaft comprises multiple lumen formed therein to slidably receive the needle electrodes 24 a, 24 b, or 824 a-m. A flexible sheath extends longitudinally from a handle portion to the distal end. The handle portion comprises multiple slide members received in respective slots defining respective walls. The slide members are coupled to the respective needle electrodes 24 a, 24 b, or 824 a-m. The slide members are movable to advance and retract the electrode 24 a, 24 b, or 824 a-m. The needle electrodes 24 a, 24 b, or 824 a-m, may be independently movable by way of the respective slide members. The needle electrodes 24 a, 24 b, or 824 a-m, may be deployed independently or simultaneously. An electrical ablation device (not shown) comprising an elongated flexible shaft to house multiple needle electrodes and a suitable handle is described in commonly owned U.S. patent application Ser. No. 11/897,676 titled “ELECTRICAL ABLATION SURGICAL INSTRUMENTS,” filed Aug. 31, 2007, now U.S. Patent Application Publication No. 2009/0062788, the entire disclosure of which is incorporated herein by reference in its entirety.

It will be appreciated that the embodiments of the electrical ablation devices 20, 800 described with referenced to FIGS. 2A-D and 3, may be introduced inside a patient endoscopically, transcutaneously, percutaneously, through an open incision, through a trocar (as shown in FIG. 4), through a natural orifice, or any combination thereof. In one embodiment, the outside diameter of the electrical ablation devices 20, 800 may be sized to fit within a working channel of an endoscope and in other embodiments the outside diameter of the electrical ablation devices 20, 800 may be sized to fit within a hollow outer sleeve 620, or trocar, as shown in FIG. 4, for example. The hollow outer sleeve 620 or trocar is inserted into the upper gastrointestinal tract of a patient and may be sized to also receive a flexible endoscopic portion of an endoscope 622 (e.g., gastroscope), similar to the endoscope 12 described in FIG. 1.

FIG. 4 illustrates one embodiment of the electrical ablation system 10 shown in FIG. 1 in use to treat undesirable tissue 48 located in the liver 50. The undesirable tissue 48 may be representative of a variety of diseased tissues, cancers, tumors, masses, lesions, abnormal tissue growths, for example. In use, the electrical ablation device 20 may be introduced into or proximate the tissue treatment region through a port 52 of a trocar 54. The trocar 54 is introduced into the patient via a small incision 59 formed in the skin 56. The endoscope 12 may be introduced into the patient trans-anally through the colon, trans-vaginally, trans-orally down the esophagus and through the stomach using translumenal techniques, or through a small incision or keyhole formed through the patient's abdominal wall (e.g., the peritoneal wall). The endoscope 12 may be employed to guide and locate the distal end of the electrical ablation device 20 into or proximate the undesirable tissue 48. Prior to introducing the flexible shaft 22 through the trocar 54, the sheath 26 is slid over the flexible shaft 22 in a direction towards the distal end thereof to cover the electrodes 24 a, 24 b (as shown in FIG. 2A) until the distal end of the electrical ablation device 20 reaches the undesirable tissue 48.

Once the electrical ablation device 20 has been suitably introduced into or proximate the undesirable tissue 48, the sheath 26 is retracted to expose the electrodes 24 a, 24 b (as shown in FIG. 2B) to treat the undesirable tissue 48. To ablate the undesirable tissue 48, the operator initially may locate the first electrode 24 a at a first position 58 a and the second electrode 24 b at a second position 60 using endoscopic visualization and maintaining the undesirable tissue 48 within the field of view of the flexible endoscope 12. In various embodiments, the operator may place the first and/or second electrodes 24 a, 24 b with the aid of pre-operative and/or intra-operative images such as, for example, images acquired by magnetic resonance imaging (MRI), X-ray fluorescence (XRF) imaging, ultrasound imaging and/or computed tomography (CT) imaging, for example. The pre-operative and intra-operative images can comprise a three-dimensional image of the patient's body, for example, and can aid the operator in placing the electrodes 24 a, 24 b in or proximal to the undesired tissue 48 in the tissue treatment region while maintaining a safe distance from critical structures within the body, for example. In various embodiments, the pre-operative and intra-operative images can be recorded and registered into a common coordinate system mapped to the patient's body, for example. In some embodiments, registration points can be attached to the patient's body during a pre-operative scan, for example, and can be left in place during the surgical procedure, for example. Further, in such embodiments, the electrical ablation device 20 can comprise registration points, such as registration points on the handpiece 16 (FIG. 1) and/or on the electrodes 24 a, 24 b, for example, such that the position of the electrodes 24 a, 24 b relative to registration points within the patient's body can be determined.

The first position 58 a may be near a perimeter edge of the undesirable tissue 48. Once the electrodes 24 a, 24 b are located into or proximate the undesirable tissue 48, the electrodes 24 a, 24 b are energized with irreversible electroporation pulses to create a first necrotic zone 65 a. For example, once the first and second electrodes 24 a, 24 b are located in the desired positions 60 and 58 a, the undesirable tissue 48 may be exposed to an electric field generated by energizing the first and second electrodes 24 a, 24 b with the energy source 14. The electric field may have a magnitude, frequency, and pulse length suitable to induce irreversible electroporation in the undesirable tissue 48 within the first necrotic zone 65 a. The size of the necrotic zone is substantially dependent on the size and separation of the electrodes 24 a, 24 b, as previously described. The treatment time is defined as the time that the electrodes 24 a, 24 b are activated or energized to generate the electric pulses suitable for inducing irreversible electroporation in the undesirable tissue 48.

This procedure may be repeated to destroy relatively larger portions of the undesirable tissue 48. The position 60 may be taken as a pivot point about which the first electrode 24 a may be rotated in an arc of radius “r,” the distance between the first and second electrodes 24 a, 24 b. Prior to rotating about the second electrode 24 b, the first electrode 24 a is retracted by pulling on the slide member 30 (FIGS. 1 and 2A-D) in a direction towards the proximal end and rotating the electrical ablation device 20 about the pivot point formed at position 60 by the second electrode 24 b. Once the first electrode 24 a is rotated to a second position 58 b, it is advanced to engage the undesirable tissue 48 at point 58 b by pushing on the slide member 30 in a direction towards the distal end. A second necrotic zone 65 b is formed upon energizing the first and second electrodes 24 a, 24 b. A third necrotic zone 65 c is formed by retracting the first electrode 24 a, pivoting about pivot point 60 and rotating the first electrode 24 a to a new location, advancing the first electrode 24 a into the undesirable tissue 48 and energizing the first and second electrodes 24 a, 24 b. This process may be repeated as often as necessary to create any number of necrotic zones 65 p, where p is any positive integer, within multiple circular areas of radius “r,” for example, that is suitable to ablate the entire undesirable tissue 48 region. At anytime, the surgeon or clinician can reposition the first and second electrodes 24 a, 24 b and begin the process anew. Similar techniques may be employed to ablate any other undesirable tissues that may be accessible trans-anally through the colon, and/or orally through the esophagus and the stomach using translumenal access techniques. Therefore, the embodiments are not limited in this context.

FIG. 5 illustrates a detailed view of one embodiment of the electrical ablation system 10 shown in FIG. 4 in use to treat undesirable tissue 48 located in the liver 50. The first and second electrodes 24 a, 24 b are embedded into or proximate the undesirable tissue 48 on the liver 50. The first and second electrodes 24 a, 24 b are energized to deliver one or more electrical pulses of amplitude and length sufficient to induce irreversible electroporation in the undesirable tissue 48 and create the first necrotic zone 65 a. Additional electric pulses may be applied to the tissue immediately surrounding the respective electrodes 24 a, 24 b to form second, thermal, necrotic zones 63 a,b near the electrode-tissue-interface. The duration of an irreversible electroporation energy pulse determines whether the temperature of the tissue 63 a,b immediately surrounding the respective electrodes 24 a, 24 b raises to a level sufficient to create thermal necrosis. As previously described, varying the electrode 24 a, 24 b size and spacing can control the size and shape of irreversible electroporation induced necrotic zone 65 a. Electric pulse amplitude and length can be varied to control the size and shape of the thermally induced necrotic zones near the tissue-electrode-interface.

Referring to FIGS. 6-8, in one embodiment, a probe guide 100 can be structured to guide electrodes, such as electrodes 824 a, 824 b, 824 c, 824 d (FIG. 3), in or proximal to a tissue treatment region. In various embodiments, the probe guide 100 can maintain the parallel alignment of the electrodes 824 a, 824 b, 824 c, 824 d, for example, and/or maintain a predetermined distance or gap between the electrodes 824 a, 824 b, 824 c, 824 d, for example. In some embodiments, the probe guide 100 can comprise a body portion 102 and, in various embodiments, the body portion 102 can comprise at least two passages, such as first passage 104 a and second passage 104 b, which can extend through the body portion 102. The passages 104 a, 104 b can extend through the body portion 102 from a first or proximal surface 106 to a second or tissue contacting surface 108, for example. The first passage 104 a can be structured to axially restrain the first electrode 824 a, for example, and the second passage 104 b can be structured to axially restrain the second electrode 824 b, for example. Furthermore, in various embodiments, the first passage 104 a can be parallel or substantially parallel to the second passage 104 b. Referring primarily to FIG. 8, an axis A can pass through each passage 104 a, 104 b, for example. In various embodiments, the axis A can define the central axis of each passage 104 a, 104 b. The axes A defining the first and second passages 104 a, 104 b can be separated by a predetermined distance or gap of approximately 1.0 cm to approximately 2.5 cm, for example. In some embodiments, the axes defining the first and second passages 104 a, 104 b can be separated by approximately 1.5 cm, for example.

In various embodiments the first passage 104 a can be structured to axially restrain the first electrode 824 a and the second passage 104 b can be structured to axially restrain the second electrode 824 b, for example. In some embodiments, the first and second electrodes 824 a, 824 b can comprise a proximal end and a distal end. In at least one embodiment, the distal end of the first electrode 824 a can be spaced a predetermined distance from the distal end of the second electrode 824 b when the first electrode 824 a is restrained in the first passage 104 a and the second electrode 824 b is axially restrained in the second passage 104 b, for example. The predetermined distance between the distal ends of the first and second electrodes 824 a, 824 b can correspond to a treatment distance in the tissue treatment region. In various embodiments, as described herein, the distal ends of the first and second electrodes 824 a, 824 b can be operably structured to conduct current therebetween when at least one of the first and second electrodes 824 a, 824 b is energized by an energy source 14 (FIG. 3). In various embodiments, the energy source 14 can comprise a radio frequency energy source, a pulsed radio frequency energy source, an irreversible electroporation energy source and/or a pulsed irreversible electroporation energy source, for example. In some embodiments, the current conducted between the distal ends of the first and second electrodes 824 a, 824 b can be selected to generate an electric field of approximately 1500 volts per centimeter, for example.

In at least one embodiment, the body portion 102 can comprise at least four passages, such as the first passage 104 a, the second passage 104 b, a third passage 104 b and a fourth passage 104 d; the passages 104 a, 104 b, 104 c, 104 d can extend through the body portion 102 from the first surface 106 to the second surface 108, for example. The first passage 104 a can be structured to axially restrain the first electrode 824 a, for example, the second passage 104 b can be structured to axially restrain the second electrode 824 b, for example, the third passage 104 c can be structured to axially restrain the third electrode 824 c, for example, and the fourth passage 104 d can be structured to axially restrain the fourth electrode 824 d, for example. In various embodiments the passages 104 a, 104 b, 104 c, 104 d through the body portion 102 of the probe guide 100 can be parallel and/or substantially parallel. Furthermore, as described herein, an energy source 14 (FIG. 3) can be structured to operably energize at least one of the electrodes 824 a, 824 b, 824 c, 824 d such that the electrodes 824 a, 824 b, 824 c, 824 d conduct current therebetween.

Referring primarily to the embodiment illustrated in FIG. 6, an axis A can pass through each passage 104 a, 104 b, 104 c, 104 d, for example. In various embodiments, an axis A can define the central axis of each passage 104 a, 104 b. The axes A defining the passages 104 a, 104 b, 104 c, 104 d can be separated by predetermined distance or gap of approximately 1.0 cm to approximately 2.5 cm, for example. In at least one embodiment, the axes defining the first and second passages 104 a, 104 b can be separated by approximately 1.5 cm, for example, the axes defining the second and third passages 104 b, 104 c can be separated by approximately 1.5 cm, for example, the axes defining the third and fourth passages 104 c, 104 can be separated by approximately 1.5 cm, for example, and the axes defining the fourth and first passages 104 d, 104 a can be separated by approximately 1.5 cm, for example. In at least one embodiment, the axes defining the first and third passages 104 a, 104 c can be separated by approximately 2.5 cm, for example. In various embodiments, the predetermined distances between the passages 104 a, 104 b, 104 c, 104 d may be equidistant or substantially equidistant. In other embodiments, the at least two predetermined distances between the passages 104 a, 104 b, 104 c, 104 d can be different. In various embodiments, the axes defining the passages 104 a, 104 b, 104 c, 104 d can correspond with the edges of a parallelogram in the body portion 102 of the probe guide 100, for example. In various embodiments, the parallelogram can be substantially cubic and/or rectangular, for example. Referring primarily to FIG. 8, the passages 104 a, 104 b can comprise an inner surface 118 that define the bores through the body portion 102 of the probe guide 100. In various embodiments, referring to FIG. 8, for example, the inner surface can comprise a radiopaque material such as, for example, a metallic sleeve or a metallic surface coating. In various embodiments, the inner surface 118 can comprise a longitudinal track 120 that comprises the radiopaque material, for example, an embedded metal wire or rod, or a metal sleeve filled with plastic.

In some embodiments, the probe guide 100 can comprise a rim 114 at and/or near the first surface 106 of the probe guide 100. In various embodiments, the probe guide 100 can also comprise a base 110 at and/or near the second surface 108 of the probe guide 100. In some embodiments, the base 110 and/or the rim 114 can comprise a substantially circular, elliptical or polygonal perimeter. For example, the base 110 can comprise a circular perimeter 112. The base 110 and/or the rim 114 can comprise a wider cross-sectional area than the body portion 102 of the probe guide 100, for example. Furthermore, the base 110 and/or the rim 114 can extend peripherally from an outer surface 126 of the body portion 102 of the probe guide 100, for example. In various embodiments, the probe guide 100 can also comprise an extension 116 extending from the body portion 102. In various embodiments, the extension 116 can comprise the second or tissue contacting surface 108 of the probe guide 100. The extension 116 can comprise a cross-sectional area that is smaller than, larger than, or approximately equal to the cross-sectional area of the base 110 and/or the body portion 102, for example.

During use, an operator may desire to position multiple electrodes, such as the first electrode 824 a, the second electrode 824 b, the third electrode 824 c, and/or the fourth electrode 824 d in or proximal to a tissue treatment region. Further, the operator may desire that the electrodes 824 a, 824 b, 824 c, and/or 824 d are separated by a predetermined distance or distances when positioned in or proximal to the tissue treatment region, for example. In some embodiments, the probe guide 100 can comprise a predetermined distance or distances between the passages 104 a, 104 b, 104 c, and/or 104 d, for example, which can correspond with a preferred treatment distance or distances between the electrodes 824 a, 824 b, 824 c, and/or 824 d, for example. In various embodiments, the operator can position the probe guide 100 relative to the tissue treatment region. In at least one embodiment, the second surface 108 and/or the base 110 of the probe guide 100 can be positioned adjacent to, abutting and/or against tissue in or proximal to the tissue treatment region. The first electrode 824 a can be axially advanced through the first passage 104 a of the probe guide 100, for example. In various embodiments, the first electrode 824 a can pierce or puncture tissue to arrive at a preferred first position in the tissue treatment region. In some embodiments, the first electrode 824 a can be positioned relative to the tissue treatment region and, subsequently, the first electrode 824 a can be positioned within the first passage 104 a of the probe guide 100, In at least one embodiment, the probe guide 100 can then be axially moved along the first electrode 824 a towards a distal position on the first electrode 824 a, in which the probe guide 100 is positioned adjacent to, against, and/or abutting tissue in or proximal to the tissue treatment region.

When the first electrode 824 a and the probe guide 100 are appropriately positioned relative to tissue in the tissue treatment region, the distal end of the second electrode 824 b can be axially advanced through the second passage 104 b of the probe guide 100, for example. As the distal end of the second electrode 824 b is advanced through the second passage 104 b, the second passage 1804 b can guide the second electrode 824 b a predetermined distance from the distal end of the first electrode 824 a, for example, and/or along a path parallel or substantially parallel to the first electrode 824 a, for example. In various embodiments, the distal end of the third electrode 824 c can be similarly advanced through the third passage 104 c of the probe guide 100 and/or the distal end of the fourth electrode 824 d can be similarly advanced through the fourth passage 104 d of the probe guide. The second electrode 824 b, the third electrode 824 c, and the fourth electrode 824 d can be advanced simultaneously, consecutively, or a combination thereof. As the distal end of the third electrode 824 c is advanced through the third passage 104 c, the third passage 104 c can guide the third electrode 824 c a predetermined distance from the distal end of the first electrode 824 a and/or the second electrode 824 b, for example, and/or along a path parallel or substantially parallel to the first electrode 824 a and/or the second electrode 824 b, for example. Similarly, as the distal end of the fourth electrode 824 d is advanced through the fourth passage 104 d, the fourth passage 104 d can guide the fourth electrode 824 d a predetermined distance from the distal end of the first electrode 824 a, the second electrode 824 b and/or the third electrode 824 c, for example, and/or along a path parallel or substantially parallel to the first electrode 824 a, the second electrode 824 b and/or the third electrode 824 c, for example. Once the electrodes 824 a, 824 b, 824 c, 824 d are positioned in the tissue treatment region, the electrodes 824 a, 824 b, 824 c, 824 d can define a first target treatment zone or necrotic zone 65 a (FIG. 4) in the tissue treatment region.

As described herein, in particular with the embodiments of the electrodes illustrated in FIG. 3, at least one electrode 824 a, 824 b, 824 c, 824 d can be energized by an energy source 14 such that the electrodes 824 a, 824 b, 824 c, 824 d conduct current therebetween. In various embodiments, the current can non-thermally ablate tissue in the first target treatment zone in the tissue treatment region, for example. In some embodiments, the electrodes 824 a, 824 b, 824 c, 824 d can be withdrawn from the probe guide 100, which can then be repositioned relative to the tissue treatment region, for example. The probe guide 100 can be pivoted and/or translated, for example. In various embodiments, the electrodes 824 a, 824 b, 824 c, 824 d can then be re-advanced through the passages 104 a, 104 b, 104 c, 104 d to treat tissue in a second target treatment zone in the tissue treatment region, for example. The process can be repeated for a multiple target treatment zones until all tissue in the tissue treatment region has been treated by the electrical ablation device 800 (FIG. 3), for example.

Referring now to FIG. 56, in one embodiment, a probe guide 150 can comprise a body portion 152 having a plurality of passages, such as first passage 154 a, second passage 154 b, third passage 154 c, and fourth passage 154 d; the passages 154 a, 154 b, 154 c, 154 d can extend through the body portion 152 from a first surface 156 to a second or tissue contacting surface, for example. In various embodiments, the body portion 152 can be substantially rectangular and may comprise rounded corners, for example. The first passage 154 a can be structured to axially restrain the first electrode 824 a, for example, the second passage 154 b can be structured to axially restrain the second electrode 824 b, for example, the third passage 154 c can be structured to axially restrain the third electrode 824 c, for example, and the fourth passage 154 d can be structured to axially restrain the fourth electrode 824 d, for example. Similar to embodiments described herein, the passages 154 a, 154 b, 154 c, 154 d through the body portion 152 of the probe guide 150 can be parallel and/or substantially parallel and can be separated by a predetermined distance or distances of approximately 1.0 cm to 2.5 cm, for example. Furthermore, as described herein, an energy source 14 (FIG. 3) can be structured to operably energize at least one of the electrodes 824 a, 824 b, 824 c, 824 d such that the electrodes 824 a, 824 b, 824 c, 824 d conduct current therebetween.

In the embodiment illustrated in FIG. 56, the body portion 152 can comprise an outer surface 176. In at least one embodiment, the outer surface 176 can comprise a contour 172 directed into the body portion 152, for example. In various embodiments, the outer surface 176 can comprise a plurality of contours 172. The body portion 152 can comprise a first contour 172 on a first side of the body portion 152, for example, and a second contour 172 on a second side of the body portion 152, for example. In various embodiments, the contour 172 on the first side of the body 152 can extend into the body 152 towards the contour 172 on the second side of the body portion 152, for example. The contour(s) 172 can provide a gripping surface for the operator to grasp, position, and/or hold the probe guide 150 relative to tissue in the tissue treatment region. In some embodiments, the probe guide 150 can also comprise a rim and/or a base 162, which can be similar to rim 114 and base 110, described in herein.

Referring now to FIGS. 9 and 10, in one embodiment, a probe guide 200 can comprise a body portion 202 and a handle 224, for example. In various embodiments, the body portion 202 can comprise a plurality of passages, such as first passage 204 a, second passage 204 b, third passage 204 b and fourth passage 204 d; the passages 204 a, 204 b, 204 c, 204 d can extend through the body portion 202 from a first surface 206 to a second or tissue contacting surface 208, for example. The first passage 204 a can be structured to axially restrain the first electrode 824 a, for example, the second passage 204 b can be structured to axially restrain the second electrode 824 b, for example, the third passage 204 c can be structured to axially restrain the third electrode 824 c, for example, and the fourth passage 204 d can be structured to axially restrain the fourth electrode 824 d, for example. Similar to embodiments described herein, the passages 204 a, 204 b, 204 c, 204 d through the body portion 102 of the probe guide 100 can be parallel and/or substantially parallel and can be separated by a predetermined distance or distances of approximately 1.0 cm to 2.5 cm, for example. Furthermore, as described herein, an energy source 14 (FIG. 3) can be structured to operably energize at least one of the electrodes 824 a, 824 b, 824 c, 824 d such that the electrodes 824 a, 824 b, 824 c, 824 d conduct current therebetween.

In the embodiments illustrated in FIGS. 9 and 10, the body portion 202 can comprise an outer surface 226. In at least one embodiment, the outer surface 226 can comprise a contour 222 directed into the body portion 202, for example. In various embodiments, the outer surface 226 can comprise a plurality of contours 222. The body portion 202 can comprise a first contour 222 on a first side of the body portion 202, for example, and a second contour 222 on a second side of the body portion 202, for example. In various embodiments, the contour 222 on the first side of the body 202 can extend into the body 202 towards the contour 222 on the second side of the body portion 202, for example. In some embodiments, the probe guide 200 can also comprise a rim 214 and/or a base, such as rim 114 and base 110, described in herein. In various embodiments, the probe guide 200 can comprise a handle 224 extending from the body portion 202 of the probe guide 200. The handle 224 can comprise a substantially accurate profile, for example, a substantially flat profile, for example, or a combination thereof. In various embodiments, the handle 224 can comprise an ergonomic shape or grip.

Similar to other embodiments described herein, the probe guide 200, illustrated in FIGS. 9 and 10, for example, can be positioned in or proximal to the tissue treatment region. In various embodiments, the tissue contacting surface 208 can be positioned adjacent to, against, and/or abutting tissue in the tissue treatment region, for example. In various embodiments, the handle 224 and/or the contours 222 can facilitate accurate positioning of the body portion 202 of the probe guide 200 relative to a target treatment zone in the tissue treatment region. Similar to other embodiments, once the probe guide 200 is positioned relative to the tissue treatment region, the first electrode 824 a can be advanced through the first passage 204 a, for example, the second electrode 824 b can be advanced through the second passage 204 b, for example, the third electrode 824 c can be advanced through the third passage 204 c, for example, and/or the fourth electrode 824 d can be advanced though the fourth passage 204 d, for example. In various embodiments, the handle 224 and/or contours 222 can facilitate steadiness of the body portion 202 of the probe guide 200 relative to the tissue treatment region as the electrodes 824 a, 824 b, 824 c and/or 824 d are advanced through the passages 204 a, 204 b, 204 c and/or 204 d of the body portion 202.

In various embodiments, referring primarily to FIG. 11, in one embodiment, a probe guide 300 can comprise a substantially cylindrical body 302 having a first or top surface 306 and a second or bottom surface 308. In various embodiments, at least one surface 306, 308 can comprise a substantially conical shape. Referring to FIG. 11, the first surface 306 can comprise a substantially conical shape, for example. The probe guide 300 can also comprise a plurality of passages 304 a, 304 b, 304 c, 304 d configured to axially restrain the electrodes 824 a, 824 b, 824 c, 824 d, similar to other embodiments described herein. In various embodiments, the cylindrical body 302 can comprise a plurality of openings or channels 316 therethrough. For example, four openings 316 can extend from the first, conical surface 306 through the body 302 to the second surface 308, for example. The openings 316 can provide a channel for heat and/steam to escape or vent from the tissue treatment region, for example, when current is conducted between the electrodes 824 a, 824 b, 824 c, 824 d, as described herein. In various embodiments, the guide 300 can also comprise a central bore 314. In some embodiments, the central bore 314 can provide the clinician with a central reference point for positioning the probe guide 300 and the electrode probes 824 a, 824 b, 824 c and/or 824 d relative to a target treatment zone in a tissue treatment region. For example, the central bore 314 can be positioned at or near a central position in the target treatment zone. The electrodes 824 a, 824 b, 824 c, and/or 824 d can be positioned within the passages 204 a, 204 b, 204 c, and/or 204 d of the probe guide 400 such that the electrodes 824 a, 824 b, 824 c, and/or 824 d surround the central position in the target treatment zone, for example.

Referring now to FIGS. 12-14, in one embodiment, a probe guide 400 can comprise the cylindrical body 302 described herein. In various embodiments, the probe guide 400 can also comprise a base 410. The base 410 can extend from the second or bottom surface 308 of the cylindrical body 302, for example. In some embodiments, the base 410 can be connected to the body portion 302 by flanges or ribs 420. In various embodiments, at least two ribs 420 can extend from the cylindrical body 302 to the base 410, for example. In other embodiments, at least four ribs 420 can extend between the base 410 and the cylindrical body 302. In such embodiments, a space or gap can be positioned between portions of the cylindrical body 302 and portions of the base 410, for example. In other embodiments, the base 410 can peripherally extend from the cylindrical body 302 such that no spaces or gaps are positioned between the cylindrical body 302 and the base 410. In various embodiments, the base 410 can comprise a tissue contacting surface 408 (FIG. 13) that is structured to operably abut tissue when the electrodes 824 a, 824 b, 824 c, 824 d are positioned relative to a tissue treatment region, as described herein. In at least one embodiment, the tissue contacting surface 408 of the base 410 can help to steady the cylindrical body 302 relative to the tissue treatment region.

Referring to FIG. 15, in one embodiment, a probe guide 500 can comprise a body portion 502 and, in various embodiments, a plurality of passages can extend through the body portion 502. The passages can extend from a first or top surface 506 to a second or tissue contacting surface (not shown), for example. In some embodiments, two passages, such as a first passage 504 a and a second passage 504 b, can extend through the body portion 502. In other embodiments, at least four passages, such as passages 504 a, 504 b, 504 c, 504 d, can extend through the body portion 502 from the first surface 506 to the second surface. The passages 504 a, 504 b, 504 c, 504 d can be configured to axially restrain the electrodes 824 a, 824 b, 824 c, 824 d, for example, and/or guide the electrodes 824 a, 824 b, 824 c, 824 d in parallel or substantially parallel alignment, for example, similar to other embodiments described herein.

In various embodiments, the body portion 502 can comprise an outer surface 526. In some embodiments, at least one contour 522 can extend into the body portion 502 from the outer surface 526, for example. The contour 522 can be structured to provide a grip and holding means for the clinician to engage when positioning and/or steadying the probe guide 500 relative to the tissue treatment region. In various embodiments, a contour 522 can be positioned on a first side of the body 502 and another contour 522 can be positioned on a second side of the body portion 502, for example. Referring still to FIG. 15, in various embodiments, the passages 504 a, 504 b, 504 c, 504 d through the body portion 502 can be clustered together at or near a first end 514 of the body portion 502. In such embodiments, a section of the body portion 502 can extend away from the passages 504 a, 504 b, 504 c, 504 d and towards a second end 516 of the body portion 502. In some embodiments, a significant section of the body 502 can extend away from the passages 504 a, 504 b, 504 c, 504 d and towards the second end 516. In various embodiments, the body portion 502 at the second end 516 can provide a significant tissue contacting surface (not shown) to position against tissue in the tissue treatment region, for example. In at least one embodiment, at least one contour 522 in the outer surface 526 of the body portion 502 can be position at or near the second end 516 and around the tissue contacting surface of the body 502. The extended tissue contacting surface and/or contours 522 can help the operator position and/or steady the probe guide 500 relative to the tissue treatment region.

Referring now to FIG. 16, in one embodiment, a probe guide 600 can comprise the body portion 502 as described herein. In the embodiments illustrated in FIG. 16, the probe guide 600 can also comprise a base 610 that extends from the body portion 502, for example. In various embodiments, the base 610 can be pivotally connected to the body portion 502. The base 610 can be pivotally connected to the body portion 502 by a pivot joint, pivot pin, and/or pivot shaft, for example. In various embodiments, a pivot shaft such as pivot shaft 612 can extend between the base 610 and the body portion 502 to enable pivoting of the body portion 502 relative to the base 610. In such embodiments, a tissue contacting surface (not shown) on the base 610 can be positioned adjacent to, abutting and/or against tissue in the tissue treatment region; furthermore, the body portion 502, including the passages 504 a, 504 b, 504 c, 504 d therethrough, can pivot relative to the base 610.

Similar to other embodiments described herein, the probe guide 600 can be positioned relative to the tissue treatment region and the first electrode 824 a can be axially advanced through the first passage 504 a, for example. In various embodiments, the contours 522 can help the operator engage or grip the body portion 602 of the probe guide 600 and position the body portion 602 relative to the first target treatment zone in the tissue treatment region. As described herein, once the probe guide 600 and the first electrode 824 a are positioned relative to the tissue treatment region, the second electrode 824 b can be advanced through the second passage 504 b, for example, the third electrode 824 c can be advanced through the third passage 504 c, for example, and/or the fourth electrode 824 d can be advanced though the fourth passage 504 d, for example. The electrodes 824 a, 824 b, 824 c, 824 d can be positioned relative to the tissue treatment region such that a current conducted therebetween treats tissue in a first target zone.

In various embodiments, the electrodes 824 a, 824 b, 824 c, 824 d can be withdrawn from the body portion 502 of the probe guide 600 and from the first target treatment zone. The body portion 502 of the probe guide 600 and the passages 504 a, 504 b, 504 c, 504 d therethrough can pivot on the pivot shaft 612 relative to the base 610. In such embodiments, the tissue contacting surface on the base 610 can remain stationary or significantly stationary relative to the tissue treatment region. In other embodiments, referring again to the embodiment illustrated in FIG. 15, the tissue contacting surface on the body portion 502 can be lifted and/or pivoted relative to the tissue treatment region, for example. In various embodiments, once the body portion 502 of the probe guide 600 has pivoted to a new position, the electrodes 824 a, 824 b, 824 c, 824 d can be axially advanced through the passages 504 a, 504 b, 504 c, 504 d, respectively, as described herein. In various embodiments, the electrodes 824 a, 824 b, 824 c, 824 d can be positioned relative to the tissue treatment region such that a current conducted therebetween treats tissue in a second target treatment zone. In at least one embodiment, the electrodes 824 a, 824 b, 824 c, 824 d can be re-withdrawn, the body portion 502 can pivot, and the electrodes 824 a, 824 b, 824 c, 824 d can be re-advanced to treat tissue in another target treatment zone. In some embodiments, the process can be repeated until tissue throughout the tissue treatment region has been treated by the electrical ablation device 800 (FIG. 3), for example.

Referring to FIG. 17, in one embodiment, a probe guide 700 can comprise a first body portion 701 and a second body portion 702. In various embodiments, a first passage 703 can extend through the first body portion, for example, and a second passage 704 can extend through the second body portion 702, for example. In various embodiments, the first passage 703 can be structured to axially restrain the first electrode 24 a (FIG. 1), for example, and the second passage 704 can be structured to axially restrain the second electrode 24 b, for example. In some embodiments, the distal end of the first electrode 24 a can be spaced a predetermined distance from the distal end of the second electrode 24 b when the first electrode 24 a is axially restrained in the first passage 703 and the second electrode 24 b is axially restrained in the second passage 704. Further, the predetermined distance between the distal ends of the first and second electrodes 24 a, 24 b can correspond to a treatment distance in the tissue treatment region. The distal ends of the first and second electrodes 24 a, 24 b can be operatively structured to conduct currents therebetween when at least one of the first and second electrodes 24 a, 24 b is energized by an energy source 14 (FIG. 1), for example.

In the embodiments illustrated in FIG. 17, a connecting portion or flange 714 can connect the first body portion 701 and the second body portion 702. The length of the connecting portion 714 can affect the predetermined distance between the first and second passages 703, 704, for example. In various embodiments, the first and/or second body portions 701, 702 can comprise as substantially cylindrical shape. In at least one embodiment, the first body portion 701 can comprise a semi-cylindrical shape and a triangular shape, for example. The height of the first body portion 701 can be greater than, less than, or substantially equal to the height of the second body portion 702. In various embodiments, the connecting portion 714 can comprise a sloped or angled surface that connects the first and second body portions 701, 702.

In various embodiments, the first body portion 701 can comprise a first slot 716 extending from the first passage 703 to an outer surface 706 of the first body portion 701. The first slot 716 can reach the outer surface 706 at a first outlet 708, for example. In various embodiments, the first electrode 24 a (FIG. 1) can be axially restrained in the first passage 703. Further, the first electrode 24 a can be removed from the first passage 703 through the first slot 716 in the first body portion 701. In various embodiments, the first passage 703 can comprise a first width and the first slot 716 can comprise a minimum width. In various embodiments, the minimum width of the first slot 716 can substantially equal the first width of the first passage 703. In such embodiments, the first electrode 24 a can easily and smoothly move in and out of the first passage 703 through the first slot 716. In other embodiments, the minimum width of the first slot 716 can be less than or greater than the first width of the first passage 703. In embodiments where the minimum width of the first slot 716 is less than the first width of the first passage 703, the first slot 716 can restrict movement of the first electrode 24 a in and/or out of the first passage 703. In various embodiments, the first electrode 24 a must be aligned with the first slot 716 and pulled through the first slot 716 to move the first electrode 24 a into and/or out of first passage 703 of the first body portion 701. In some embodiments, a force must be applied to move the first electrode 24 a in and/or out of the first passage 703.

Similarly, in various embodiments, the second body portion 702 can comprise a second slot 718 extending from the second passage 704 to an outer surface 710 of the second body portion 702. The second slot 718 can reach the outer surface 710 at a second outlet 712, for example. In various embodiments, the second electrode 24 b (FIG. 1) can be axially restrained in the second passage 704. Further, the second electrode 24 b can be removed from the second passage 704 through the second slot 718 in the second body portion 702. In various embodiments, the second passage 704 can comprise a second width and the second slot 718 can comprise a minimum width. In various embodiments, the minimum width of the second slot 718 can substantially equal the second width of the second passage 704. In such embodiments, the second electrode 24 b can easily and smoothly move in and out of the second passage 704 through the second slot 718. In other embodiments, the minimum width of the second slot 718 can be less than or greater than the second width of the second passage 704. In embodiments where the minimum width of the second slot 718 is less than the second width of the second passage 707, the second slot 718 can restrict movement of the second electrode 24 b in and/or out of the second passage 704. In various embodiments, the second electrode 24 b must be aligned with the second slot 718 and pulled through the second slot 718 to move the second electrode 24 b into and/or out of second passage 704 of the second body portion 702. In some embodiments, a force must be applied to move the second electrode 24 b in and/or out of the second passage 704.

In various embodiments, the first slot 716 can be substantially orthogonal to the second slot 718, for example. In other embodiments, the slots 716, 718 can be substantially aligned and/or angularly offset from each other by less than or more than approximately 90 degrees, for example. In various embodiments, at least one of the first and second slots 716, 718 can be substantially flared. The first slot 716 can be flared such that the first slot 716 widens as the first slot 716 extends from the first passage 703 to the outer surface 706, for example. Additionally or alternatively, the second slot 718 can be flared such that the second slot 718 widens as the second slot 718 extends from the second passage 704 to the outer surface 710, for example. In various embodiments, an orthogonal or angled arrangement of the entry outlets 708, 712 can facilitate entry and/or repositioning of the electrodes 24 a, 24 b, relative to the tissue treatment region.

Similar to the embodiments described herein in connection with FIGS. 6-16, for example, the probe guide 700 can be positioned relative to this tissue treatment region and the first and second electrodes 24 a, 24 b can be axially advanced through the first and second passages 703, 704, respectively. The first and second electrodes 24 a, 24 b can be positioned in the tissue treatment region and the first and second passages 703, 704 can maintain parallel alignment of the first and second electrodes 24 a, 24 b, for example, and/or maintain a predetermined treatment distance. As described herein, current can be conducted between the first and second electrodes 24 a, 24 b to treat tissue in the target treatment zone positioned therebetween. In various embodiments, at least one of the first and second electrodes 24 a, 24 b can be withdrawn from its respective passage 703, 704 and moved to another position. For example, the second electrode 24 b can be removed from the second passage 704 through the second slot 718, for example. The second body portion 702 can then be pivoted relative to the first body portion 701 before the second electrode 24 b is axially advanced through the second passage 704 and into the tissue treatment region, for example. In various embodiments, the minimum width of the first slot 716 can prevent the first electrode 24 a from moving out of the first passage 703 as the second body portion 702 pivots relative thereto.

In various embodiments, the first and second body portions 701, 702 of the probe guide 700 can be positioned relative to the tissue treatment region before the first and/or second electrodes 24 a, 24 b are positioned relative to the tissue treatment region. For example, when the probe guide 700 is positioned relative to a tissue treatment region, the first electrode 24 a can be axially advanced through the first passage 703 or moved through the first slot 706 into the first passage 703, for example. In various embodiments, the flanged shape of the first slot 716 and facilitate entry of the first electrode through the minimum width of the first slot 716 and into the first passage 703, for example. The second electrode 24 b can then be drawn through the second slot 718 and into the second passage 704, for example.

Referring to FIG. 18, a probe guide 850 can comprise the second body portion 702 and connecting flange 714 as described herein. Further, in various embodiments, the probe guide 850 can comprise a first body portion 801. The first body portion 801 can comprise a first passage 803 structured to axially restrain a first electrode, for example. The first passage 803 need not comprise a slot and/or outlet to an outer surface 806 of the first body portion 800, for example. In such embodiments, similar to the embodiments described herein, once the first electrode 24 a and the first body portion 801 are positioned relative to the tissue treatment region, the second body portion 702 can be pivoted relative to the first body portion 801 such that the passages 803, 704 are appropriately positioned relative to the tissue treatment region. In various embodiments, the second electrode can be axially advanced through the second passage 704 and/or laterally advanced through the second slot 718 and current can be conducted through the distal ends of the first and second electrodes 24 a, 24 b to treat tissue therebetween. In various embodiments, the second electrode can then be axially withdrawn through the second passage 704 and/or laterally withdrawn through the second slot 718, for example. In some embodiments, the second body portion 702 can then be pivoted relative to the first body portion 801 before the second electrode 24 b is re-advanced through the second body portion 702 to treat another tissue zone in the tissue treatment region.

Referring to FIG. 19, in one embodiment, a probe guide 900 can comprise a body 902 having an outer perimeter 906. The probe guide 900 can comprise a substantially flat disc and/or may comprise a substantial height. In various embodiments, the outer perimeter 906 can comprise a plurality of contours 908. The perimeter 906 can comprise a first contour 908 a, a second contour 908 b, a third contour 908 c, a fourth contour 908 d, and a fifth contour 908 e, for example. In various embodiments, the body 902 can comprise a passage 904 structured to axially restrain the first electrode 24 a. A groove 920 can extend between the passage 904 and the outer perimeter 906 of the body 902, for example. In various embodiments, the groove 920 can be structured to permit movement of the first electrode 24 a therethrough. In various embodiments, a radius R can extend from the passage 904 to the outer perimeter 906 of the body 902. In some embodiments, the radius R can vary at each contour 908 around the outer perimeter 906 of the body 902. For example, a first radius R_(a) can extend between the passage 904 and the first contour 908 a, for example, a second radius R_(b) can extend from the passage 904 to the second contour 908 b, for example, and a third radius R_(b) can extend from the passage 904 to the third contour 908 c, for example.

In various embodiments, as described herein, a second electrode 24 b can be positioned along a contour 908 of the perimeter 906. Furthermore, in various embodiments, a distal end of the first electrode 24 a can be spaced from a distal end of the second electrode 24 b by the variable radius R when the first electrode 24 a is axially restrained in the passage 904 and the second electrode 24 b is positioned along a contour 908 of the outer perimeter 906, for example. In various embodiments, the probe guide 900 can hold the electrodes 24 a, 24 b in axial alignment with each other when the first electrode 24 a is axially restrained in the passage 904 and the second electrode 24 b is positioned along a contour 908. Further, in various embodiments, the radius R can correspond to a treatment distance in the tissue treatment region. Furthermore, as described herein, the distal ends of the first and second electrodes 24 a, 24 b can be operatively structured to conduct current therebetween when at least one of the first and second electrodes 24 a, 24 b is energized by an energy source 14 (FIG. 1).

In various embodiments, the body 902 can also comprise a plurality of traversing edges 910. In various embodiments, a traversing edge 910 can be positioned between two adjacent contours 908 around the perimeter 906 of the body 902. A traversing edge 910 can be positioned between the first and second contours 908 a, 908 b, for example. In various embodiments, the traversing edge 910 can comprise a substantially straight edge. In other embodiments, the traversing edge 910 can comprise a curve or contour. In some embodiments, a curved traversing edge can correspond with the perimeter of the second electrode 24 b such that the curved traversing edge can receive and hold the second electrode 24 b in position along a contour 908 of the outer perimeter 906. Furthermore referring still to FIG. 19, the probe guide 900 can comprise indicia of measurements 612 that enable the operator to determine the treatment distance between the first electrode and the second electrode. For example, the electrode probe guide 900 can comprise length measurement such as centimeters, millimeters and/or inches to indicate the length of the radius around the perimeter 906 of the body 902. The first radius R_(a) can correspond to 10 mm, for example, the second radius R_(b) can correspond to 11 mm, for example, the third radius R_(c) can correspond to 12 mm, for example, the fourth radius R_(d) can correspond to 13 mm, for example, and the fifth radius R_(e) can correspond to 14 mm, for example.

Similar to other embodiments described herein, the first electrode 24 a can be positioned within the passage 904 of the probe guide 900. The first electrode 24 a can laterally traverse the groove 920, for example, and/or axially translate through the passage 904, for example, when the probe guide 900 is positioned relative to the tissue treatment region. In various embodiments, once the probe guide 900 and the first electrode 24 a are positioned relative to the tissue treatment region, the second electrode 24 b can be positioned along a contour 908 such that the radius R corresponds with the preferred tissue treatment distance. In various embodiments, the electrical ablation device 800 can be used with the probe guide 900. In such embodiments, the passage 804 can axially restrain the first electrode 824 a and the second, third and/or fourth electrodes 824 b, 824 c, 824 d can be positioned along a contour of the probe guide 900, for example. The electrodes 824 a, 824 b, 824 c, 824 d can be positioned relative to the tissue treatment region such that a current conducted therebetween treats tissue in the target treatment zone of the tissue treatment region.

Referring now to FIGS. 20 and 21, a probe guide 1000 can comprise a body portion 1002 and a bore 1014 extending therethrough. In various embodiments, the body portion 1002 can comprise a top surface 1006 and a bottom surface (not shown). The bore 1014 can extend from the top surface 1006 to the bottom surface, for example. In various embodiments, the body 1002 can comprise a plurality of enclosures. The body 1002 can have two enclosures 1010 a, 1010 c, for example, or four enclosures 1010 a, 1010 b, 1010 c, 1010 d, for example. The body portion 1002 can comprise a number of enclosures 1010 that equals the number of electrodes that the probe guide 1000 is structured to axially restrain, for example. In various embodiments, a passage 1004 a, 1004 b, 1004 c, 1004 d can extend through each enclosure 1010 a, 1010 b, 1010 c, 1010 d from the top surface 1006 to the bottom surface of the body portion 1002, for example. Similar to the other embodiments described herein, each passage 1004 a, 1004 b, 1004 c, 1004 d can be structured to axially restrain an electrode positioned therein. Further, the passages 1004 a, 1004 b, 1004 c, 1004 d can be substantially parallel such that the electrodes 824 a, 824 b, 824 c, 824 d (FIG. 3) are held in a parallel or substantially parallel arrangement by the probe guide 1000, for example. The enclosures 1010 a, 1010 b, 1010 c, 1010 d can be spaced equidistance or non-equidistance around the perimeter of the body portion 1002. In some embodiments, the enclosures 1010 a, 1010 b, 1010 c, 1010 d can be positioned around the perimeter of the body portion 1002 such that the passages 1004 a, 1004 b, 1004 c, 1004 d through the enclosures 1010 a, 1010 b, 1010 c, 1010 d, respectively, are positioned a predetermined distance or distances from each other.

In various embodiments, the probe guide 1000 can also comprise a plurality of ribs 1020. The ribs 1020 can extend between adjacent enclosures 1010 of the body 1002. In various embodiments, the ribs can laterally traverse between the first enclosure 1010 a and the fourth enclosure 1010 d, for example. The probe guide 1000 can also comprise an outer surface 1016. A plurality of vents 1018 can extend from the outer surface 1016 to the bore 1014 through the body portion 1002, for example. In various embodiments, the vents 1018 can be positioned between two adjacent ribs 1020 of the body portion 1002. In various embodiments, the probe guide 1000 can comprise four enclosures 1010 positioned around the perimeter of the body portion 1002, for example. In various embodiments, a first plurality of ribs and/or vents 1018 can be positioned between the first and fourth enclosures 1010 a, 1010 d of the body portion 1002. Furthermore, a second plurality of ribs 1020 and/or vents 1018 can be positioned between the second and third enclosures 1010 b, 1010 c of the body portion 1002, for example. Referring to FIG. 20, the body portion 1002 can also comprise a contour or grip 1022. In various embodiments, the body portion 1002 can comprise a plurality of contours or grips 1022 therein. In some embodiments, a first grip 1022 can be positioned on a first side of the body portion 1002 between the first and fourth enclosures 1010 a, 1010 d, for example, and a second grip 1022 can be positioned on a second side of the body portion 1002 between the second and third enclosures 1010 b, 1010 c, for example. In various embodiments, the contours 1022 can provide a grip for the operator to engage or hold when placing the probe guide 1000 relative to the tissue treatment region, for example.

Referring now to FIGS. 22-27, a probe guide 1100 can comprise a body portion 1102, similar to the body portion 1002 described herein. The body portion 1102 can comprise first, second, third and fourth enclosures 1110 a, 1110 b, 1110 c, 1110 d similar to enclosures 1010 a, 1010 b, 1010 c, 1010, for example, and/or first, second, third, and fourth passages 1104 a, 1104 b, 1104 c, 1104 d similar to passages 1004 a, 1004 b, 1004 c, 1004 d. The probe guide 1100 can also comprise a handle 1124 and/or a locking element 1132, for example. In various embodiments, the handle 1124 can be removable. In other embodiments, the handle 1124 can be fixedly secured to the body portion 1102. Referring primarily to FIG. 23, the handle 1124 can comprise an extension 1126 that extends from the handle 1124 to a distal portion 1128 thereof. In various embodiments, an orifice 1130 can extend through at least a portion of the extension 1126, for example. Referring primarily to FIG. 22, the extension 1126 can be positioned within the body portion 1102 of the probe guide 1100. In such embodiments, the extension 1126 can be positioned through at least a portion of a proximal opening 1112 (FIG. 26) in the body portion 1102, for example. Furthermore, in various embodiments the distal portion 1028 of the handle 1124 can extend through a bore 1114 of the body portion and into a distal opening 1113 (FIG. 25) in the body portion 1102, for example. In such embodiments, the orifice 1130 on the extension 1126 of the handle 1124 can be aligned with the bore 1114 of the body portion 1102. In various embodiments, referring primarily to FIG. 24, a locking element 1132 can comprise a plunger or shaft 1134 and a rib 1136. In various embodiments, at least a portion of the locking element 1132 can be positioned within the bore 1114 of the body 1102. When a portion of the locking element 1132 is positioned within the bore 1114, the locking element 1132 can secure or lock the handle 1124 to the body portion 1202, for example. In some embodiments, the plunger 1134 can extend through the orifice 1130 of the handle 1124 to lock the handle 1124 in place.

Similar to embodiments described herein, the probe guide 1100 can be positioned relative to the tissue treatment region and the first electrode 824 a can be axially advanced through the first passage 1104 a of the probe guide 1100, for example. In various embodiments, the handle 1124 and/or contours 1120 can facilitate accurate positioning of the body portion 1102 of the probe guide 1100 relative to the first electrode 824 a and/or the target zone in the tissue treatment region. As described herein, once the probe guide 1100 and the first electrode 824 a are positioned relative to the tissue treatment region, the second electrode 824 b, the third electrode 824 c, and/or the fourth electrode 824 d can be advanced though passages 1104 b, 1104 c, 1104 d, respectively, of the probe guide 1100. In various embodiments, the handle 1124 and/or contours 1120 can facilitate steadiness of the body portion 1102 of the probe guide 1100 as electrodes 824 b, 824 c and/or 824 d are advanced through the passages 1104 of the body portion 1102.

Referring now to FIGS. 28-34, a probe guide 1200 can comprise a first body portion 1201 and a second body portion 1202. In some embodiments, the probe guide 1200 can also comprise at least one spring element 1240 positioned between the first body portion 1201 and the second body portion 1202, for example. The probe guide can comprise two spring elements 1240, for example, and the spring elements 1240 can comprise coil springs, for example. In various embodiments, the spring elements 1240 can be movable from an initial configuration to at least one deformed configuration.

Referring primarily to FIG. 30, the first body portion 1201 can comprise a plurality of first catches 1208, 1210. In various embodiments, the plurality of first catches 1208, 1210 can extend from the first side and/or the second side of the first body portion 1201. In some embodiments, at least one first side first catch 1208 can be positioned on a first side of the first body portion 1201, for example, and at least one second side first catch 1210 can be positioned on a second side of the first body portion 1201, for example. Referring still to FIG. 30, the first body portion 1201 can comprise an inner surface 1220. In some embodiments, when the first body portion 1201 is positioned relative to the second body portion 1202 (FIGS. 28 and 29), the inner surface 1220 can be positioned adjacent to the second body portion 1202. In some embodiments, the inner surface 1220 can be positioned adjacent to an inner surface 1222 on the second body portion 1202 (FIG. 31). When the first body portion 1201 is positioned relative to the second body portion 1202, the plurality of first catches 1208, 1210 can extend from the inner surface 1220 of the first body portion 1201 towards the second body portion 1202, for example. As described herein, the first catches 1208, 1210 can each comprise a hooked extension (FIG. 29). The first catches 1208, 1210 and/or the hook(s) 1216 can form channels 1204 a, 1204 b (FIG. 29) configured to restrain the electrodes 24 a, 24 b (FIG. 1), as described herein. Referring again to FIG. 30, the inner surface 1220 of the first body portion 1201 can also comprise an orifice 1238 and/or at least one opening or depression 1224. As described herein, the orifice 1238 can be configured to receive the shaft of a screw 1230, for example, and the depression 1224 can be configured to receive a spring element 1240, for example.

Referring still to FIG. 30, the plurality of first catches 1208, 1210, can comprise a plurality of first side first catches 1208 and/or a plurality of second side first catches 1210, for example. The first side first catches 1208 can comprise an “A” first side first catch 1208 a, a “B” first side first catch 1208 b, and/or a “C” first side first catch 1208 c, for example. In other embodiments, the plurality of first side first catches 1208 can comprise additional and/or fewer first side first catches 1208. Furthermore, the first side first catches 1208 a, 1208 b, 1208 c can be positioned along the first side of the first body portion 1201 and can be separated by a gap 1218 between each first side first catch 1208 a, 1208 b, 1208 c. For example, a gap 1218 can be positioned between the “A” first side first catch 1208 a and the “B” first side first catch 1208 b, for example. Similarly, the second side of the first body portion 1201 can comprise a plurality of second side first catches 1210. The plurality of second side first catches 1210 can comprise an “A” second side first catch 1210 a, a “B” second side first catch 1210 b, and/or a “C” second side first catch 1210 c, for example. Similar to the description above, the plurality of second side first catches 1210 can comprise additional and/or fewer second side first catches 1210, for example. Additionally, in various embodiments, gaps 1218 can be positioned between adjacent second side first catches 1210 a, 1210 b, 1210 c. For example, a gap 1218 can be positioned between the “B” second side first catch 1210 b and the “C” second side first catch 1210 c.

Referring primarily to FIG. 31, the second body portion 1202 can comprise a plurality of second catches 1212, 1214. In various embodiments, the plurality of second catches 1212, 1214 can extend from the first side and/or the second side of the second body portion 1202. In some embodiments, at least one first side second catch 1212 can be positioned on a first side of the second body portion 1202, for example, and at least one second side second catch 1214 can be positioned on a second side of the second body portion 1202, for example. Referring still to FIG. 31, the second body portion 1202 can comprise an inner surface 1222. In some embodiments, when the second body portion 1202 is positioned relative to the first body portion 1201 (FIGS. 28 and 29), the inner surface 1222 can be positioned adjacent to the first body portion 1201. In some embodiments, the inner surface 1222 can be positioned adjacent to the inner surface 1220 on the first body portion 1201 (FIG. 30). When the second body portion 1202 is positioned relative to the first body portion 1201, the plurality of second catches 1212, 1214 can extend from the inner surface 1222 of the second body portion 1202 towards the first body portion 1201, for example. As described herein, the second catches 1212, 1214 can each comprise a hooked extension (FIG. 29). The second catches 1212, 1214 and/or the hook(s) 1216 can form channels 1204 a, 1204 b (FIG. 29) configured to restrain electrodes 24 a, 24 b (FIG. 1), as described herein. Referring primarily to FIG. 33, the inner surface 1222 of the second body portion 1202 can also comprise an orifice 1239 and/or at least one depression or opening 1226. As described herein, the orifice 1239 can be configured to receive the shaft of a screw 1230, for example, and the depression 1226 can be configured to receive a spring element 1240, for example.

Referring to FIG. 31, the plurality of second catches 1212, 1214, can comprise a plurality of first side second catches 1212 and/or a plurality of second side second catches 1214, for example. The first side second catches 1212 can comprise an “A” first side second catch 1212 a, a “B” first side second catch 1212 b, and/or a “C” first side second catch 1212 c, for example. In other embodiments, the plurality of first side second catches 1212 can comprise additional and/or fewer first side second catches 1212. Furthermore, the first side second catches 1208 a, 1208 b, 1208 c can be positioned along the first side of the second body portion 1202 and can be separated by a gap 1218 between each first side second catch 1212 a, 1212 b, 1212 c. For example, a gap 1218 can be positioned between the “A” first side second catch 1212 a and the “B” first side second catch 1212 b, for example. Similarly, the second side of the second body portion 1202 can comprise a plurality of second side second catches 1214. The plurality of second side second catches 1214 can comprise an “A” second side second catch 1214 a, a “B” second side second catch 1214 b, and/or a “C” second side second catch 1214 c, for example. Similar to the description above, the plurality of second side second catches 1214 can comprise additional and/or fewer second side first catches 1214, for example. Additionally, in various embodiments, gaps 1218 can be positioned between adjacent second side second catches 1214 a, 1214 b, 1214 c, for example. For example, a gap 1218 can be positioned between the “B” second side second catch 1214 b and the “C” second side second catch 1214 c.

Referring now to FIG. 32, the fastener 1230 can comprise threads 1232 and/or a head 1234, for example. In some embodiments, referring again to FIGS. 28 and 29, the fastener 1230 can attach the first body portion 1201 to the second body portion 1202. As described herein, the fastener 1230 can extend through an orifice 1238 in the first body portion 1201 and an orifice 1239 in the second body portion 1202, for example. The inner surface 1220 of the first body portion 1201 and the inner surface 1222 of the second body portion 1202 can be defined by the amount the screw and/or screws 1230 are threadably engaged with the first and/or second body portions 1201, 1202. For example, the fastener(s) 1230 can be tightened such that the gap between the inner surface 1220 of the first body portion 1201 and the inner surface 1222 of the second body portion 1202 is reduced. In other embodiments, the fastener(s) 1230 can be loosened such that the gap between the inner surface 1220 of the first body portion 1201 and the inner surface 1222 of the second body portion 1202 is increased. In other embodiments, the first and second body portions 1201, 1202 can be secured together by non-threaded fasteners.

Referring primarily to FIGS. 29 and 33, the probe guide 1200 can comprise the spring element 1240, which can be positioned in the depression 1226 in the inner surface 1224 of the second body portion 1202. In various embodiments, the spring element 1240 can extend towards the first body portion 1201, for example. When the fastener(s) 1230 secure the first body portion to the second body portion, the spring element or elements 1240 can be restrained therebetween. In various embodiments, the spring element(s) can be compressed between the first and second body portions 1201, 1202. The amount that the spring element(s) 1240 are compressed can depend on the fasteners 1230 and the gap between the first and second body portions 1201, 1202, for example. In at least one embodiment, the threaded fasteners 1240 can be tightened to reduce the gap between the body portions 1201, 1202, for example, and to compress the spring elements 1240 more, for example. The threaded fasteners 1240 can be loosened to increase the gap between the body portions 1201, 1202, for example, and to decompress the spring elements 1240, for example. The clamping force on the electrodes can be changed by adjusting the spring. For example, a heavier gauge wire for the spring can be used to increase the forces on the spring element.

Referring primarily to FIG. 29, in various embodiments, the plurality of first and second catches 1208, 1210, 1212, and 1214 can form the first and second channels 1204 a, 1204 b. The first channel 1204 a can be structured to restrain the first electrode 24 a when the spring 1240 is in the initial configuration, for example, and the second channel 1204 b can be structured to restrain the second electrode 24 b when the spring 1240 is in the initial configuration, for example. In some embodiments, the first side first catches 1208 a, 1208 b, 1208 c and the first side second catches 1212 a, 1212 b, 1212 c can form the first channel 1204 a that is configured to restrain the first electrode 24A. Similarly, the second side first catches 1210 a, 1210 b, 1210 c and the second side second catches 1214 a, 1214 b, 1214 c can form the second channel 1204 b that is configured to restrain the second electrode 24B, for example. In such embodiments, the first channel 1204 a can be positioned on the first side of the first body portion 1201, for example, and the second channel 1204 b can be positioned on the second side of the first body portion 1201. Furthermore, as described herein, the distal end of the first electrode 24 a can be spaced from the distal end of the second electrode 24 b by a predetermined distance when the first electrode 24 a is axially restrained in the first channel 104 a and the second electrode 24 b is axially restrained in the second channel 104 b. The pre-determined distance can correspond to a treatment distance in the tissue treatment region. Furthermore, the distal ends of the first and second electrodes 24 a, 24 b can be operatively structured to conduct current therebetween when at least one of the first and second electrodes 24 a, 24 b is energized by an energy source 14 (FIG. 1).

In various embodiments, the first electrode 24 a can be positioned relative to the tissue treatment region. As described herein, pre-operative and intra-operative three-dimensional imaging can aid the operator in placing the first electrode 24 a in the target treatment zone of the tissue treatment region, for example. In various embodiments, once the first electrode 24 a is positioned relative to the tissue treatment region, the probe guide 1200 can be positioned around at least a portion of the first electrode 24 a. In some embodiments, to position the probe guide 1200 around at least a portion of the first electrode 24 a, the spring element 1240 can be deformed or compressed from an initial configuration to a deformed configuration such that the first channel 1204 a defined by the plurality of first side first catches 1208 and the plurality of first side second catches 1212 opens to receive the first electrode 24 a. The probe guide 1200 can be squeezed or compressed, for example, to open the channel 1204 a to receive the first electrode 24 a. In various embodiments, once the probe guide 1200 is in position relative to the first electrode 24 a, e.g., the first electrode 24 a is axially retained in the first channel 1204 a, the second electrode 24 b can be axially advanced through the second channel 1204 b defined by the plurality of second side first catches 1210 and the plurality of second side second catches 1214, for example. In other embodiments, to position the probe guide 1200 around at least a portion of the second electrode 24 b, the spring element 1240 can be deformed or compressed from an initial configuration to a deformed configuration such that the second channel 1204 b defined by the plurality of second side first catches 1210 and the plurality of second side second catches 1214 opens to receive the second electrode 24 b. In various embodiments, an actuator (not shown) can compress the spring elements 1240 to open the first and/or second channels 1204 a, 1204 b, for example. Further, in some embodiments, the actuator can decompress the spring elements 1240 to close the first and/or second channels 1204 a, 1204 b, for example. In various embodiments, when the spring element 1240 is in the initial configuration, the probe guide 1200 can exert a clamping force on the electrode 24 a, 24 b restrained therein.

In various embodiments, referring to FIGS. 35 and 36, a probe guide 1300 can comprise first and second body portions 1301, 1302 similar to the first and second body portions 1201, 1202 of probe guide 1200 described herein. Referring primarily to FIG. 35, the second body portion 1302 can comprise an opening or depression 1326 in an inner surface 1322 that is configured to receive a spring element 1340. In various embodiments, the spring element 1340 can comprise a leaf spring. Similar to other embodiments described herein, the spring element 1340 can be deformed from an initial configuration to a deformed configuration such that channel(s) defined by catches on the first and second body portions 1301, 1302, including first side second catches 1312 a, 1312 b, 1312 c, for example, and second side second catches 1314 a, 1314 b, 1314 c, for example, can open to receive the first and/or second electrodes 24 a, 24 b for example. Further, when the spring element 1340 returns to the initial configuration, the catches can close such that the channel(s) can axially restrain the first and/or second electrodes 24 a, 24 b for example.

In various embodiments, referring now to FIGS. 37-39, a probe guide 1400 can comprise a first body portion 1401 and a second body portion 1402, similar to first and second body portions 1201, 1202 of probe guide 1200 described herein. In various embodiments, a spring element (not shown) can be positioned between the first body portion 14010 and the second body portion 1402. The spring element can be a leaf spring, coil spring, or collapsible foam, for example. Similar to other embodiments described herein, the spring element can be movable from an initial configuration to deformed configurations. In various embodiments, referring primarily to FIG. 38, the first body portion can comprise a substantially flat surface with a plurality of first side second catches 1412 and a plurality of second side second catches 1414 extending therefrom. Similar to other embodiments described herein, a gap 1418 can be positioned between adjacent catches 1412, 1414. Referring primarily to FIG. 39, the plurality of first side second catches 1412 and the plurality of second side second catches 1414 can each comprise a hook or hooked extension 1416. In various embodiments, the first side second catch 1412 can extend substantially away from the second body portion 1402. However, in various embodiments, the hooked extension 1416 can extend back towards the second body portion 1402. A contour 1417 can curve around a portion of the first side second catch 1412 and/or the second side second catch 1414, for example. In various embodiments, when the first and second body portions 1401, 1402 are positioned relative to each other to form a first and second channel to receive the electrodes 24 a, 24 b, the contours 1417 can be positioned adjacent to the electrodes 24 a, 24 b, for example.

Referring now to FIGS. 40-44, a probe guide 1500 can comprise a first body portion 1501 and a second body portion 1502. In various embodiments, a spring element (not shown) can be positioned between the first and second body portions 1501, 1502. In various embodiments, referring primarily to FIGS. 41-43, the first body portion 1501 can comprise a substantially rectangular shape having a slot 1504 therethrough. In some embodiments, the slot 1504 can be rectangular or substantially rectangular. In other embodiments, the slot 1504 can be tapered, for example. Further, a flange 1508 can extend along a portion of the first body portion 1501 to a catch 1510, for example. In some embodiments, the catch 1510 can be positioned at a distal end of the first body portion 1501. In various embodiments, the catch 1510 can comprise at least one hook or hooked extension 1516 extending therefrom. Further, in at least one embodiment, the catch 1510 can comprise an angled projection 1518 extending towards the slot 1504, for example.

Referring now to FIG. 44, the second body portion 1502 can comprise a longitudinal extension 1520 and at least one leg 1522. In some embodiments, the second body portion 1502 can comprise a first leg 1522 on a first side, for example, and a second leg 1522 on a second side, for example. Further, in at least one embodiment, an end of the second body portion can comprise a taper 1524. In various embodiments, referring again to FIG. 40, the first body portion 1501 can be positioned relative to the second body portion 1502 such that the longitudinal extension 1520 fits within the slot 1504. Further, the legs 1522 of the second body portion 1502 can fit along the flange 1508 of the first body portion 1501 when the first body portion 1501 is positioned relative to the second body portion 1502, for example. In such embodiments, the second body portion 1502 can fit within the substantially T-shaped cut-out in the first body portion 1501 between the slot 1504 and the catch 1510. Further, the taper 1524 of the second body portion 1501 can be structured to receive the angled projection 1518 of the first body portion, for example.

In various embodiments, referring primarily to FIG. 40, a spring (not shown) can be positioned between at least a portion of the first body portion 1501 and a portion of the second body portion 1502. Similar to embodiments described herein, the first channel can be configured to receive the first electrode 24 a and the second channel can be configured to receive the second electrode 24 b. In various embodiments, when the spring is compressed, the channels can widen or open such that the first electrode 24 a and/or the second electrode 24 b can move into and/or out of their respective channels, for example. In such embodiments, the first electrode 24 a can be positioned relative to the tissue treatment region in a patient. Subsequently, the probe guide 1500 can be positioned around at least a portion of the first electrode 24 a, for example, by compressing the spring element and moving the second body portion 1502 relative to the first body portion 1501 such that the first channel opens to receive the first electrode 24 a, for example. Subsequently, the second electrode 24 b can be axially advanced through the second channel formed between the first body portion 1501 and the second body portion 1502. When the spring returns or seeks to return to its pre-compressed configuration, the probe guide 1500 can exert a clamping force on the first and second electrodes 24 a, 24 b restrained therein.

Referring to FIGS. 45-47, a probe guide 1600 can comprise a first body portion 1602 a and a second body portion 1602 b. In various embodiments, referring primarily to FIG. 47, the first body portion 1602 a can comprise a first end first catch 1608 and a second end first catch 1610. The first end first catch 1608 can be positioned at or near a first distal end of the first body portion 1602 a, for example, and the second end first catch 1610 can be positioned at or near a second distal end of the first body portion 1602 a, for example. In various embodiments, the first end first catch 1608 and the second end first catch 1610 can each comprise an arcuate contour 1620 such that the first body portion 1602 a turns or bends in a first direction at the first distal end and in a second direction at the second distal end. In some embodiments, the first direction can be an opposite or substantially opposite direction to the second direction. Further, in various embodiments, the second body portion 1602 b can comprise a first end second catch 1612 and a second end second catch 1614. The first end second catch 1612 can be positioned at or near a first distal end of the second body portion 1602 b, for example, and the second end second catch 1614 can be positioned at or near a second distal end of the second body portion 1602 b, for example. In various embodiments, the first end second catch 1612 and the second end second catch 1614 can each comprise an arcuate contour 1620 such that the second body portion 1602 b bends in a first direction at the first distal end and in a second direction at the second distal end. In some embodiments, the first direction can be an opposite or substantially opposite direction to the second direction.

In various embodiments, the first and second body portions 1602 a, 1602 b can be symmetrical or substantially symmetrical. Further, the first and second body portions 1602 a, 1602 b can be positioned relative to each other such that the first catches 1608, 1610 of the first body portion 1602 a and the second catches 1612, 1614 of the second body portion 1602 b can form passages through the probe guide 1600. For example, the second body portion 1602 b can be positioned relative to the first body portion 1602 a such that the first end first catch 1608 of the first body portion and the first end second catch 1612 of the second body portion 1602 b form a first passage 1604 a. Similarly, the second body portion 1602 b can be positioned relative to the first body portion 1602 a such that the second end first catch 1610 of the first body portion and the second end second catch 1614 of the second body portion 1602 b form a second passage 1604 b. Similar to embodiments described herein, the first passage 1604 a can be structured to axially restrain the first electrode 24 a, for example, and the second passage 1604 b can be structured to axially restrain the second electrode 24 b, for example.

In various embodiments, at least one of the first body portion 1602 a and the second body portion 1602 b can be pivotable. In various embodiments, the first body portion 1602 a can pivot relative to the second body portion 1602 b. In some embodiments, the first and second body portions 1602 a, 1602 b can be structured to pivot. The first body portion 1602 a can pivot from an open guide position to a closed guide position, for example. In some embodiments, the first and second body portions 1602 a, 1602 b can pivot from the open guide position to the closed guide position. In various embodiments, when the first body portion 1602 a is pivoted to the open guide position, a first outlet or opening (not shown) can open or expand. The first opening can extend from the first passage 1604 a to an outer surface 1610 of the probe guide 1600, for example. In various embodiments, the first opening can be structured to receive the first electrode 24 a (FIG. 1) when the first body portion 1602 a is pivoted to the open position. Further, the first opening can permit movement of the first electrode 24 a out of the first passage 1604 a. In various embodiments, when the first body portion 1602 a is pivoted to the closed position, the first opening can narrow or close such that the first opening cannot receive the first electrode 24 a therethrough and the first electrode 24 a cannot move in or out of the first passage 1604 a.

In various embodiments, when the first body portion 1602 a is pivoted to the open position, a second opening (not shown) can open or expand. The second opening can extend from the second passage 1604 b to an outer surface 1610 of the probe guide 1600. In various embodiments, the second opening can be structured to receive the second electrode 24 b (FIG. 1) when the first body portion 1602 a is pivoted to the open position. Further, the second opening can permit movement of the second electrode 24 b out of the second passage 1604 b. In various embodiments, when the first body portion 1602 a is pivoted to the closed position, the second opening can narrow or close such that the second opening cannot receive the second electrode 24 b therethrough and the second electrode 24 b cannot move in or out of the second passage 1604 b.

In various embodiments, the probe guide 1600 can comprise an actuator (not shown). The actuator can pivot the first body portion between the open guide and closed guide positions. Further, in some embodiments, the actuator can be positioned in the hand piece 16 of the electrical ablation device 20 (FIG. 1). In some embodiments, the probe guide 1600 can also comprise a shell (not shown) structured to hold the first body portion 1602 a relative to the second body portion 1602 b. Furthermore, the probe guide 1600 can comprise additional body portions. For example, the probe guide can comprise a third body portion 1602 c and a fourth body portion 1602 d. In various embodiments, at least one of the first, second, third, and fourth body portions 1602 a, 1602 b, 1602 c, 1602 d can be symmetrical with another body portion 1602 a, 1602 b, 1602 c, 1602 d, for example.

Similar to embodiments described herein, the distal end of the first electrode 24 a (FIG. 1) can be spaced from the distal end of the second electrode 24 b (FIG. 1) by a predetermined distance when the first electrode 24 a is axially restrained in the first passage 1604 a and the second electrode 24 b is axially restrained in the second passage 1604 b, for example. Further, the predetermined distance can correspond to a treatment distance in a tissue treatment region. In at least one embodiment, the distal ends of the first and second electrodes 24 a, 24 b can be operably structured to conduct current therebetween when at least one of the first and second electrodes 24 a, 24 b is energized by an energy source 14 (FIG. 1), as described herein. During use, an operator can position the first electrode 24 a relative to the tissue treatment region. As described herein, pre-operative and intra-operative three-dimensional imaging can aid the operator in placing the first electrode 24 a in the target treatment zone of the tissue treatment region, for example. In various embodiments, the operator can puncture diseased tissue with the distal end of the first electrode 24 a, for example, and insert at least a portion of the first electrode 24 a therethrough. The distal end of the first electrode 24 a can be inserted into the diseased tissue a predetermined depth, for example. Once the first electrode 24 a is in place relative to the tissue treatment region, the operator may desire to position the second electrode 24 b at a second position relative to the tissue treatment region such that a treatment distance is defined between the distal ends of the first and second electrodes 24 a, 24 b. A probe guide, such as probe guide 1600, for example, can be selected. In various embodiments, the selected probe guide 1600 can comprise a predetermined distance between the first and second passages 1604 a, 1604 b, which can correspond with a preferred treatment distance. The operator may pivot at least one of the first body portion 1602 a and second body portion such that the first opening opens the first passage 1604 a to the outer surface 1610 of the probe guide 1600. In at least one embodiment, the operator may engage an actuator to open or enlarge the first passage 1604 a to the outer surface 1610. Upon opening or enlarging the first passage 1604 a to the outer surface 1610 of the probe guide 1600, the first electrode 24 a can pass through the first opening to the first passage 1604 a. Once the first electrode 24 a is positioned in the first passage 1604 a, the operator can pivot at least one of the first body portion 1602 a and the second body portion 1602 b such that the first opening narrows or closes the first passage 1604 a to the outer surface 1610 of the probe guide 1600. The narrowed or closed first passage 1604 a can axially restrain the first electrode 24 a therein.

In various embodiments, the second passage 1604 b can be defined through at least a portion of the probe guide 1600 when at least one of the first body portion 1602 a and second body portion 1602 b is pivoted to the closed position. In such embodiments, the second opening may be closed or narrowed such that the second electrode 24 b can be axially restrained in the second passage 1604 b. In various embodiments, when the first and/or second body portions 1602 a, 1602 b are pivoted to the closed position, the distal end of the second electrode 24 b can be axially advanced through the second passage 1604 b to the tissue treatment region. As the distal end of the second electrode 24 b is advanced through the second passage 1604 b, the second passage 1604 b can guide the second electrode 24 b a predetermined distance from the distal end of the first electrode 24 a, for example, and/or along a path parallel or substantially parallel to the first electrode 24 a, for example.

Referring to FIGS. 48-51, a probe guide 1700 can comprise a body 1702. In various embodiments, the body 1702 can comprise a resilient and/or elastomeric material such that the body 1702 seeks to return to an initial configuration when the body 1702 is deformed from the initial configuration to a deformed configuration. The body 1702 can comprise Pellethane® TPE, Santoprene™ thermoplastic vulcanizate (TPV), and/or silicone, for example. In various embodiments, the body 1702 can comprise silicone, for example, having a durometer Shore A hardness of 40-90. In at least one embodiment, referring primarily to FIG. 51, the probe guide 1700 can comprise a bore 1714 at least partially therethrough. The bore can extend from a top or proximal surface 1706 to a bottom or distal surface 1708, for example. In various embodiments, the bore 1714 can define an inner surface 1720 through the body 1702. In some embodiments, the inner surface 1720 of the bore 1714 can be deformable from an initial configuration to at least one deformed configuration. In various embodiments, the probe guide 1700 can also comprise a first passage 1704 a through the body 1702 and/or a second passage 1704 b though the body 1702. The first passage 1704 a can be positioned on a first side of the bore 1714, for example, and the second passage 1704 b can be positioned on a second side of the bore 1714, for example. In at least one embodiment, the first passage 1704 a can be structured to axially restrain the first electrode 24 a when the body 1702 and/or the inner surface 1720 of the bore 1714 is in the initial configuration (FIG. 49). Further, in at least one embodiment, the second passage 1704 b can be structured to axially restrain the second electrode 24 b when the body 1702 and/or the inner surface 1720 of the bore is in the initial configuration (FIG. 49). In various embodiments, the first electrode 24 a can be releasable from the first passage 1704 a when the body 1702 and/or the inner surface 1720 of the bore 1714 is moved from the initial configuration to a deformed configuration (FIG. 50). Further, in various embodiments, the second electrode 24 b can be releasable from the second passage 1704 b when the body 1702 and/or the inner surface 1720 of the bore 1714 is moved from the initial configuration to a deformed configuration (FIG. 50). As described herein, the first and second electrodes 24 a, 24 b can be released from the first and second passages 1704 a, 1704 b through outlets 1712 a, 1712 b, respectively.

In various embodiments, the bore 1714 can comprise a maximum diameter or width across the bore 1714. In some embodiments, the bore 1714 can comprise a substantially cubic, rhombic, or rectangular cross-sectional geometry when the body 1702 is in the initial, undeformed configuration. In other embodiments, the cross-sectional geometry of the bore 1714 can comprise a circular, elliptical, or polygonal shape. When the body 1702 and/or the inner surface 1720 of the bore 1714 is moved to a deformed configuration, the maximum width of the bore 1714 can be reduced, the maximum length across the bore 1714 can be increased, and/or the cross-sectional geometry of the bore 1714 can be altered. In various embodiments, the maximum width across the bore 1714 can be reduced, the maximum length across the bore can be increased, and the cross-sectional geometry of the bore 1714 can be changed from a substantially rhombic geometry to a substantially elongated oval geometry.

In various embodiments, the body 1702 can also comprise at least one outlet or slot 1712 a, 1712 b. In at least one embodiment, a first outlet 1712 a can extend from the outer surface 1710 of the body 1702 to at least the first passage 1704 a, for example, and a second outlet 1712 b can extend from the outer surface 1710 to at least the second passage 1704 b, for example. The first outlet 1712 a can extend from a first side of the body 1702 towards the bore 1714, for example, and the second outlet 1712 b can extend from a second side of the body towards the bore 1714, for example. In various embodiments, the geometry of the outlets 1712 a, 1712 b can be altered when the body 1702 and/or the inner surface 1720 of the bore 1714 is moved from an initial configuration to a deformed configuration. The outlets 1712 a, 1712 b can comprise an outward flare, for example, when the body 1702 and/or the inner surface of the bore 1714 is moved to a deformed configuration (FIG. 50). As described herein, altering the geometry of the outlets 1712 a, 1712 b can permit the release of the first and/or second electrodes 24 a, 24 b from the first and/or second passages 1704 a, 1704 b, respectively.

In various embodiments, the first outlet 1712 a can comprise a first minimum diameter when the body 1702 and/or the inner surface 1720 of the bore 1714 is in an initial configuration and the first outlet 1712 a can comprise a second minimum diameter when the body 1702 and/or the inner surface 1720 of the bore 1714 is in a deformed configuration. In at least one embodiment, the first minimum diameter can be less than the second minimum diameter. Further, in various embodiments, the first minimum diameter can be less than the diameter of the first electrode 24 a, for example, and the second minimum diameter can be greater than the diameter of the first electrode 24 a, for example. In such embodiments, the first electrode 24 a can move through the first outlet 1712 a when the body 1702 and/or the inner surface 1720 of the bore 1714 is in a deformed configuration, for example. Further, the first electrode 24 a can be restrained in the first passage 1704 a when the body 1702 and/or the inner surface 1720 of the bore 1714 is in the initial configuration, i.e., the first electrode 24 a cannot move or fit through the first outlet 1712 a, for example. In some embodiments, the first minimum diameter of the first outlet 1712 a can substantially match the diameter of the first electrode 24 a and, in various embodiments, the first outlet 1712 a can apply a clamping force to the first electrode 24 a to hold the first electrode 24 a in position when the body 1702 and/or the inner surface 1720 of the bore 1714 is in the initial configuration.

Similarly, in various embodiments, the second outlet 1712 b can comprise a first minimum diameter when the body 1702 and/or the inner surface 1720 of the bore 1714 is in an initial configuration and the second outlet 1712 b can comprise a second minimum diameter when the body 1702 and/or the inner surface 1720 of the bore 1714 is in a deformed configuration. In at least one embodiment, the first minimum diameter can be less than the second minimum diameter. Further, in various embodiments, the first minimum diameter can be less than the diameter of the second electrode 24 b, for example, and the second minimum diameter can be greater than the diameter of the second electrode 24 b, for example. In such embodiments, the second electrode 24 b can move through the second outlet 1712 b when the body 1702 and/or the inner surface 1720 of the bore 1714 is in a deformed configuration, for example. Further, the second electrode 24 b can be restrained in the second passage 1704 b when the body 1702 and/or the inner surface 1720 of the bore 1714 is in the initial configuration, i.e., the second electrode 24 b cannot move or fit through the second outlet 1712 b, for example. In some embodiments, the first minimum diameter of the second outlet 1712 b can substantially match the diameter of the second electrode 24 b and, in various embodiments, the second outlet 1712 b can apply a clamping force to the second electrode 24 b to hold the second electrode 24 b in position when the body 1702 and/or the inner surface 1720 of the bore 1714 is in the initial configuration.

Similar to embodiments described herein, the distal end of the first electrode 24 a can be spaced from a distal end of the second electrode 24 b by a predetermined distance when the first electrode 24 a is axially restrained in the first passage 1704 a and the second electrode 24 b is axially restrained in the second passage 1704 b, for example. Further, the predetermined distance can correspond to a treatment distance in a tissue treatment region. In at least one embodiment, the distal ends of the first and second electrodes 24 a, 24 b can be operably structured to conduct current therebetween when at least one of the first and second electrodes 24 a, 24 b is energized by an energy source 14 (FIG. 1), as described herein. During use, an operator can position the first electrode 24 a relative to the tissue treatment region. As described herein, pre-operative and intra-operative three-dimensional imaging can aid the operator in placing the first electrode 24 a in the target treatment zone of the tissue treatment region, for example. Once the first electrode 24 a is in place relative to the tissue treatment region, the operator may desire to position the second electrode 24 b at a second position relative to the tissue treatment region such that a treatment distance is defined between the distal ends of the first and second electrodes 24 a, 24 b, for example. A probe guide, such as probe guide 1700, for example, can be selected by the operator. In various embodiments, the selected probe guide 1700 can comprise a predetermined distance between the first and second passages 1704 a, 1704 b, which can correspond with a preferred treatment distance between electrodes 24 a, 24 b. The operator may deform the body 1702 and/or the inner surface 1720 of the bore 1714 from the initial configuration to a deformed configuration such that the geometry of the first outlet 1712 a changes to accommodate the first electrode 24 a therethrough (FIG. 50). Upon deforming the probe guide 1700, the first electrode 24 a can pass through the first outlet 1712 a to the first passage 1704 a. Once the first electrode 24 a is positioned in the first passage 1704 a, the operator can release the body 1702 of the probe guide 1700. In at least one embodiment, the body 1702 can seek to return to the initial, undeformed configuration when released by the operator, for example (FIG. 49). Further, the probe guide 1700 can substantially return to the initial, undeformed configuration such that the first and second passages 1704 a, 1704 b are structured to axially restrain the first and second electrodes 24 a, 24 b, respectively.

In various embodiments, the second passage 1704 b can be defined through at least a portion of the probe guide 1700 when the body 1702 and/or the inner surface 1720 of the bore 1714 returns or substantially returns to the initial, undeformed configuration (FIG. 49). In such embodiments, the second outlet 1712 b may be closed or narrowed such that the second electrode 24 b can be axially restrained in the second passage 1704 b, i.e., the second electrode 24 b cannot move through the second outlet 1712 b out of the second passage 1704 b. In various embodiments, when the body 1702 has substantially returned in the initial configuration, the distal end of the second electrode 24 b can be axially advanced through the second passage 1704 b to the tissue treatment region. As the distal end of the second electrode 24 b is advanced through the second passage 1704 b, the second passage 1704 b can guide the second electrode 24 b a predetermined distance from the distal end of the first electrode 24 a, for example, and/or along a path parallel or substantially parallel to the first electrode 24 a, for example.

Referring primarily to FIG. 52, the probe guide 1700 can be manufactured by a molding technique, for example. In various embodiments, a frame 1750 can comprise a top 1752 and a bottom 1754. In some embodiments, a mold 1760 can comprise an upper portion 1762, a lower portion 1764, a first side portion 1766, a second side portion 1768 and/or a central portion 1770, for example. In at least one embodiment, the lower portion 1764 of the mold 1760 can be removably positioned in the bottom 1754 of the frame 1750, for example, and/or the upper portion 1762 of the mold 1760 can be removably positioned in the top 1752 of the frame 1750, for example. The upper portion 1762 of the mold 1760 can comprise a surface that corresponds to the outer surface 1710 of the body 1702 of the probe guide 1700, for example. Further, the lower portion 1764 of the mold 1760 can comprise a surface that corresponds to the outer surface 1710 of the body 1702 of the probe guide 1700, for example. In at least one embodiment, at least a portion of the second side portion 1766 can comprise a geometry that corresponds to the geometry of the second outlet 1712 b and/or the second passage 1704 b, for example. Further, at least a portion of the first side portion 1768 can comprise a geometry that at least substantially corresponds to the geometry of the first outlet 1712 a and/or the first passage 1704 a, for example.

In various embodiments, the upper portion 1762, the lower portion 1764, the first side portion 1766, and the second side portion 1768 can be positioned between the top 1752 and the bottom 1754 of the frame 1750. Further, the central portion 1770 can be positioned between the upper portion 1762, the lower portion 1764, the first side portion 1766 and the second side portion 1768. The central portion 1770 can be held or retained in place by a pin or bracket in an end wall (not shown) of the frame 1750, for example. In at least one embodiment, once the mold 1760 is positioned in the frame 1750, the material forming the body 1702 of the probe guide 1700 can be added to the frame 1750. The body material 1702 can be fluidic when added to the frame 1750. In various embodiments, the body material can be poured into the frame 1750 and can flow around the first and second side portions 1766, 1768 and the central portion 1770, for example. In various embodiments, after the body material cures, or at least sufficiently cures, the body 1702 of the probe guide 1700 can be removed from the frame 1750.

Referring to FIGS. 53 and 54, a probe guide 1800 can comprise a body 1802. In various embodiments, the body 1802 can comprise a resilient and/or elastomeric material such that the body 1802 seeks to return to an initial configuration when the body is deformed from the initial configuration to a deformed configuration. The body 1802 can comprise Pellethane® TPE, Santoprene™ thermoplastic vulcanizate (TPV), and/or silicone, for example. In various embodiments, the body 1702 can comprise silicone, for example, having a durometer Shore A hardness of 40-90. In at least one embodiment, the probe guide 1800 can comprise a bore 1814 at least partially therethrough. The bore 1814 can extend from a top or proximal surface 1806 to a bottom or distal surface (not shown), for example. In various embodiments, the bore 1814 can define an inner surface 1820 through the body 1802. In some embodiments, the inner surface 1820 of the bore 1814 can be deformable from an initial configuration to at least one deformed configuration. In various embodiments, the probe guide 1800 can also comprise a first passage 1804 a through the body 1802 and/or a second passage 1804 b though the body 1802. The first passage 1804 a can be positioned on a first side of the bore 1814, for example, and the second passage 1804 b can be positioned on a second side of the bore 1814, for example. In at least one embodiment, the first passage 1804 a can be structured to axially restrain the first electrode 24 a (FIG. 1) when the body 1802 and/or the inner surface 1820 of the bore 1814 is in the initial configuration (FIG. 53). Further, in at least one embodiment, the second passage 1804 b can be structured to axially restrain the second electrode 24 b (FIG. 1) when the body 1802 and/or the inner surface 1820 of the bore 1814 is in the initial configuration (FIG. 53). In various embodiments, the first electrode 24 a can be releasable from the first passage 1804 a when the body 1802 and/or the inner surface 1820 of the bore 1814 is moved from the initial configuration to a deformed configuration (FIG. 54). Further, in various embodiments, the second electrode 24 b can be releasable from the second passage 1804 b when the body 1802 and/or the inner surface 1820 of the bore 1814 is moved from the initial configuration to a deformed configuration (FIG. 54). As described herein, the first and second electrodes 24 a, 24 b can be released from the first and second passages 1804 a, 1804 b through outlets 1812 a, 1812 b, respectively. Deformation of the body 1802 and/or the inner surface 1820 of the bore 1814 can open the first passage 1804 a, the second passage 1804 b or both passages 1804 a, 1804 b, for example, to permit the release of the first electrode 24 a, the second electrode 24 b and/or both electrodes 24 a, 24 b, respectively.

In various embodiments, the inner surface 1820 of the bore 1814 can comprise a first edge 1815 and a second edge 1816. The first edge 1815 can be angularly offset from the second edge 1816 when the inner surface 1820 is in the initial configuration, for example. Further, the first edge 1815 can substantial abut or be substantially flush with the second edge 1816 when the inner surface 1820 is in a first deformed configuration, for example. Similarly, in various embodiments, the inner surface 1820 of the bore 1814 can comprise a third edge 1822 and a fourth edge 1824. The third edge 1822 can be angularly offset from the fourth edge 1824 when the inner surface in the initial configuration, for example. Further, the third edge 1822 can substantially abut or be substantially flush with the fourth edge 1824 when the inner surface 1820 is in a second deformed configuration. In various embodiments, the first deformed configuration can match or substantially match the second deformed configuration. In such embodiments, the first edge 1815 can be angularly offset from the second edge 1816 when the third edge 1822 is angularly offset from the fourth edge 1824, for example. Furthermore, in such embodiments, the first edge 1815 can substantially abut the second edge 1816 when the third edge 1822 substantially abuts the fourth edge 1824, for example. In various other embodiments, the first deformed configuration may not match the second deformed configuration. In such embodiments, the first edge 1815 can substantially abut the second edge 1816 even when the third edge 1822 does not substantially abut the fourth edge 1824, for example. In various embodiments, for example, the inner surface 1820 or the bore 1814 can be deformed such that the first edge 1815 substantially abuts the second edge 1816, however, despite such deformation of the inner surface 1820, the third and fourth edges 1822, 1824 can remain angularly offset, and thus, the initial minimum diameter of the second outlet 1812 b can restrain the second electrode 24 b (FIG. 1) such that the second electrode 24 b is held in the second passage 1804 b while the first electrode 24 a can move through the first outlet 1812 a. Furthermore, in various embodiments, when the first and second edges 1815, 1816 substantially abut and the third and fourth edges 1822, 824 remain angularly offset, the distance between the passages 1804 a, 1804 b can remain substantially the same.

Referring still to FIGS. 53 and 55, the body 1802 of the probe guide 1800 can comprise a plurality of body portions. The probe guide 1800 can comprise first, second, third and fourth body portions 1802 a, 1802 b, 1802 c, 1802 d, for example. In various embodiments, flanges 1830 can extend between at least two adjacent body portions. A flange 1830 can extend between the second and the third body portions 1802 b, 1802 c, for example, and another flange 1830 can extend between the fourth and the first body portions 1802 d, 1802 a, for example. In various embodiments, at least one of the flanges 1830 and/or the body portions 1802 comprises a resilient and/or elastomeric material. In various embodiments, at least two adjacent body portions can be attached at a flexible joint 1832. For example, the first and second body portions 1802 a, 1802 b can be attached at a flexible joint 1832 and the third and fourth body portions 1802 c, 1802 d can be attached at a flexible joint 1832, for example. In various embodiments, the flexible joints 1832 can permit the attached body portions to hinge relative to each other.

Referring primarily to FIG. 53, in at least one embodiment, the first passage 1804 a and/or the first outlet 1812 a can be formed between the first and second body portions 1802 a, 1802 b. The first outlet 1812 a can comprise an initial minimum diameter D_(a) when the inner surface 1820 of the bore 1814 is in the initial configuration, for example. In at least one embodiment, the initial minimum diameter D_(a) of the first outlet 1812 a can restrain the first electrode 24 a (FIG. 1) such that the first electrode 24 a is held in the first passage 1804 a. Referring now to FIG. 54, when the inner surface 1820 of the bore 1814 is moved to a first deformed configuration, the first outlet 1812 a can comprise a deformed minimum diameter D_(a)′, for example. The deformed minimum diameter D_(a)′ be larger than the initial minimum diameter D_(a) such that the first outlet 1812 a can permit movement of the first electrode 24 a in or out of the first passage 1804 a, for example.

Additionally or alternatively, the second passage 1804 c and/or the second outlet 1812 b can be formed between the third and fourth body portions 1802 c, 1802 d. The second outlet 1812 a can comprise an initial minimum diameter when the inner surface 1820 of the bore 1814 is in the initial configuration, for example. In at least one embodiment, the initial minimum diameter of the second outlet 1812 b can restrain the second electrode 24 b such that the second electrode 24 b is held in the second passage 1804 b. When the inner surface 1820 is moved to a second deformed configuration, the second outlet 1812 b can comprise a deformed minimum diameter, which can be larger than the initial minimum diameter such that the second outlet 1812 b can permit movement of the second electrode 24 b in or out of the second passage 1804 b, for example.

Similar to embodiments described herein, the distal end of the first electrode 24 a (FIG. 1) can be spaced from a distal end of the second electrode 24 b (FIG. 1) by a predetermined distance when the first electrode 24 a is axially restrained in the first passage 1804 a and the second electrode 24 b is axially restrained in the second passage 1804 b, for example. Further, the predetermined distance can correspond to a treatment distance in a tissue treatment region. In at least one embodiment, the distal ends of the first and second electrodes 24 a, 24 b can be operably structured to conduct current therebetween when at least one of the first and second electrodes 24 a, 24 b is energized by an energy source 14 (FIG. 1), as described herein. During use, an operator can position the first electrode 24 a relative to the tissue treatment region. As described herein, pre-operative and intra-operative three-dimensional imaging can aid the operator in placing the first electrode 24 a in the target treatment zone of the tissue treatment region, for example. Once the first electrode 24 a is in place relative to the tissue treatment region, the operator may desire to position the second electrode 24 b at a second position relative to the tissue treatment region such that a treatment distance is defined between the distal ends of the first and second electrodes 24 a, 24 b, for example. A probe guide, such as probe guide 1800, for example, can be selected by the operator. In various embodiments, the selected probe guide 1800 can comprise a predetermined distance between the first and second passages 1804 a, 1804 b, which can correspond with a preferred treatment distance between electrodes 24 a, 24 b. The operator may deform the body 1802 and/or the inner surface 1820 of the bore 1814 from the initial configuration (FIG. 53) to a deformed configuration (FIG. 54) wherein the geometry of the first outlet 1812 a changes to accommodate the first electrode 24 a therethrough. Upon deforming the probe guide 1800, the first electrode 24 a can pass through the first outlet 1812 a to the first passage 1804 a. Once the first electrode 24 a is positioned in the first passage 1804 a, the operator can release the body 1802 of the probe guide 1800. In various embodiments, the body 1802 can seek to return to the initial, undeformed configuration (FIG. 53) when released by the operator, for example. Further, the probe guide 1800 can return or substantially return to the initial, undeformed configuration such that the first and second passages 1804 a, 1804 b are structured to axially restrain the first and second electrodes 24 a, 24 b, respectively.

In various embodiments, the second passage 1804 b can be defined through at least a portion of the probe guide 1800 when the body 1802 and/or the inner surface 1820 of the bore 1814 returns or substantially returns to the initial, undeformed configuration (FIG. 53). In such embodiments, the second outlet 1812 b may be closed or narrowed such that the second electrode 24 b can be axially restrained in the second passage 1804 b, i.e., the second electrode 24 b cannot move through the second outlet 1812 b in or out of the second passage 1804 b. In various embodiments, when the body 1802 has returned or substantially returned in the initial configuration, the distal end of the second electrode 24 b can be axially advanced through the second passage 1804 b to the tissue treatment region. As the distal end of the second electrode 24 b is advanced through the second passage 1804 b, the second passage 1804 b can guide the second electrode 24 b a predetermined distance from the distal end of the first electrode 24 a, for example, and/or along a path substantially parallel to the first electrode 24 a, for example. In other embodiments, the body 1802 and/or the inner surface 1820 of the bore 1814 can be deformed such that the second outlet 1812 b opens or enlarges to permit lateral movement of the second electrode 24 b therethrough to the second passage 1804 b. Subsequently, the body 1802 can be released and the body 1802 can return or substantially return to the initial, undeformed configuration (FIG. 53), wherein the first and second electrodes 24 a, 24 b are axially restrained in the first and second passages 1804 a, 1804 b, respectively.

Referring to FIG. 55, a probe guide 1900 can comprise a body 1902. In various embodiments, the body 1902 can comprise a resilient and/or elastomeric material such that the body 1902 seeks to return to an initial configuration when the body is deformed from the initial configuration to a deformed configuration. The body 1902 can comprise Pellethane® TPE, Santoprene™ thermoplastic vulcanizate (TPV), and/or silicone, for example. In various embodiments, the body 1702 can comprise silicone, for example, having a durometer Shore A hardness of 40-90. In at least one embodiment, the probe guide 1900 can comprise a bore 1914 at least partially extending through the body 1902. The bore 1914 can extend from a top or proximal surface 1906 to a bottom or distal surface (not shown), for example. In various embodiments, the bore 1914 can define an inner surface 1920 through the body 1902. In some embodiments, the inner surface 1920 of the bore 1914 can be deformable from an initial configuration to at least one deformed configuration. In various embodiments, the probe guide 1900 can also comprise a first passage 1904 a through the body 1902 and/or a second passage 1904 b though the body 1902. The first passage 1904 a can be positioned on a first side of the bore 1914, for example, and the second passage 1904 b can be positioned on a second side of the bore 1914, for example. In at least one embodiment, the first passage 1904 a can be structured to axially restrain the first electrode 24 a when the body 1902 and/or the inner surface 1920 of the bore 1914 is in the initial configuration (FIG. 55). Further, in at least one embodiment, the second passage 1904 b can be structured to axially restrain the second electrode 24 b when the body 1902 and/or the inner surface 1920 of the bore is in the initial configuration. In various embodiments, the first electrode 24 a can be releasable from the first passage 1904 a when the body 1902 and/or the inner surface 1920 of the bore 1914 is moved from the initial configuration to a deformed configuration (not shown). Further, in various embodiments, the second electrode 24 b can be releasable from the second passage 1904 b when the body 1902 and/or the inner surface 1920 of the bore 1914 is moved from the initial configuration to a deformed configuration. As described herein, the first and second electrodes 24 a, 24 b can be released from the first and second passages 1904 a, 1904 b through outlets (not shown).

In various embodiments, the body 1902 of the probe guide 1900 can comprise a first body portion 1902 a and a second body portion 1902 b. In at least one embodiment, the first body portion 1902 a can comprise an upper portion of the probe guide 1900, for example, and the second body portion 1902 b can comprise a lower portion of the probe guide 1900, for example. Further, in various embodiments, at least one passage 1904 a, 1904 b can be positioned between and/or adjacent to the first and second body portions 1902 b. For example, the first passage 1904 a can be positioned between the first and second body portions 1902 a, 1902 b on a first side of the bore 1914 and the second passage 1904 b can be positioned between the first and second body portions 1902 a, 1902 b on a second side of the bore 1914.

In at least one embodiment, the probe guide 1900 can also comprise a beam 1930. The beam 1903 can laterally traverse the bore 1914 from the first side to the second side of the probe guide 1900, for example. In various embodiments, the beam 1930 can comprise a substantially rigid or inflexible material such as polystyrene or a thermoplastic polymer, for example, polyethylene or polycarbonate, such as, for example, Lexan®, Makrolon®, Makroclear®. The beam 1930 can comprise a first end 1932 and a second end 1934, for example. In some embodiments, the first end 1932 can be positioned adjacent to the first passage 1904 a, for example, and the second end 1934 can be positioned adjacent to the second passage 1904 b, for example. In at least one embodiment, the first end 1932 can comprise a first groove 1936 and/or the second end 1934 can comprise a second groove 1938. The grooves 1936, 1938 can comprise an arcuate contour and/or semi-circle, for example. In various embodiments, the first groove 1936 can form a portion of the first passage 1904 a and the second groove 1938 can for a portion of the second passage 1904 b.

Referring still to FIG. 55, the beam 1930 can resist deformation when the inner surface 1920 of the bore 1914 is moved from an initial configuration to a deformed configuration. In at least one embodiment, when at least one of the body portions 1902 a, 1902 b and the inner surface 1920 of the probe guide 1900 is moved to a deformed configuration, the first and/or second passages 1904 a, 1904 b can open such that an electrode 24 a, 24 b can move into and/or out of the passages 1904 a, 1904 b, for example. In various embodiments, the first body portion 1902 a can move away from the second body portion 1902 at the first passage 1904 a, the second passage 1904 b or both passages 1904 a, 1904 b to open the passage(s) 1904 a, 1904 b to an outer surface 1926 of the probe guide 1900. As the body portions 1902 a, 1902 b and/or the inner surface 1920 of the bore 1914 are deformed, the beam 1940 can resist deformation and remain stationary in the bore 1914, for example. In various embodiments, edges and or corners on the first and/or second body portions 1902 a, 1902 b can be structured to hold the beam 1930 relative to the body portions 1902 a, 1902 b and/or the passages 1904 a, 1904 b, for example. In other embodiments, fasteners and/or adhesive may secure the beam 1930 relative to the body portions 1902 a, 1902 b and/or the passages 1904 a, 1904 b, for example.

Similar to embodiments described herein, the distal end of the first electrode 24 a (FIG. 1) can be spaced from a distal end of the second electrode 24 b (FIG. 1) by a predetermined distance when the first electrode 24 a is axially restrained in the first passage 1904 a, for example, and the second electrode 24 b is axially restrained in the second passage 1904 b, for example. Further, the predetermined distance can correspond to a treatment distance in a tissue treatment region. In at least one embodiment, the distal ends of the first and second electrodes 24 a, 24 b can be operably structured to conduct current therebetween when at least one of the first and second electrodes 24 a, 24 b is energized by an energy source 14 (FIG. 1), as described herein. During use, an operator can position the first electrode 24 a relative to the tissue treatment region. As described herein, pre-operative and intra-operative three-dimensional imaging can aid the operator in placing the first electrode 24 a in the target treatment zone of the tissue treatment region, for example. Once the first electrode 24 a is in place relative to the tissue treatment region, the operator may desire to position the second electrode 24 b at a second position relative to the tissue treatment region such that a treatment distance is defined between the distal ends of the first and second electrodes 24 a, 24 b, for example. A probe guide, such as probe guide 1900, for example, can be selected by the operator. In various embodiments, the selected probe guide 1900 can comprise a predetermined distance between the first and second passages 1904 a, 1904 b, which can correspond with a preferred treatment distance between electrodes 24 a, 24 b. The operator may deform the body 1902 and/or the inner surface 1920 of the bore 1914 from the initial configuration to a deformed configuration such that an electrode 24 a, 24 b can pass into at least one of the first and second passages 1904 a, 1904 b. Upon deforming the probe guide 1900, the first electrode 24 a can pass into the first passage 1904 a, for example. Once the first electrode 24 a is positioned in the first passage 1904 a, the operator can release the body 1902 of the probe guide 1900. In at least one embodiment, the body 1902 can seek to return to the initial, undeformed configuration when released by the operator. Further, the probe guide 1900 can substantially return to the initial, undeformed configuration such that the first and second passages 1904 a, 1904 b are structured to axially restrain the first and second electrodes 24 a, 24 b, respectively.

In various embodiments, the second passage 1904 b can be defined through at least a portion of the probe guide 1900 when the body 1902 and/or the inner surface 1920 of the bore 1914 returns or substantially returns to the initial, undeformed configuration (FIG. 55). In such embodiments, the second passage 1904 b may be closed or narrowed such that the second electrode 24 b can be axially restrained therein, i.e., the second electrode 24 b cannot move laterally into or out of the second passage 1904 b. In various embodiments, when the body 1902 has substantially returned to the initial configuration, the distal end of the second electrode 24 b can be axially advanced through the second passage 1904 b to the tissue treatment region. As the distal end of the second electrode 24 b is advanced through the second passage 1904 b, the second passage 1904 b can guide the second electrode 24 b a predetermined distance from the distal end of the first electrode 24 a, for example, and/or along a path substantially parallel to the first electrode 24 a, for example. 

1. A device for guiding electrodes relative to a tissue treatment region, wherein the device comprises: a body comprising: a first passage through the body, wherein the first passage is structured to axially restrain a first electrode, and wherein the first electrode comprises a proximal end and a distal end; and a second passage through the body, wherein the second passage is substantially parallel to the first passage, wherein the second passage is structured to axially restrain a second electrode, and wherein the second electrode comprises a proximal end and a distal end; wherein the distal end of the first electrode is spaced a predetermined distance from the distal end of the second electrode when the first electrode is restrained in the first passage and the second electrode is restrained in the second passage, wherein the predetermined distance corresponds to a treatment distance in the tissue treatment region, and wherein the distal ends of the first and second electrodes are operably structured to conduct current therebetween when at least one of the first and second electrodes is energized by an energy source.
 2. The device of claim 1, wherein the predetermined distance ranges from 1.0 centimeter to 2.0 centimeters.
 3. A system comprising: the device of claim 1; first and second electrodes restrained within the device of claim 1; and an energy source electrically coupled to the first and second electrodes.
 4. The system of claim 3, wherein the energy source comprises a Radio Frequency (RF) energy source.
 5. The system of claim 3, wherein the energy source comprises a pulsed energy source.
 6. The system of claim 3, wherein the energy source comprises an irreversible electroporation energy source.
 7. The system of claim 6, wherein the energy source comprises a pulsed energy source.
 8. The device of claim 1, wherein the current is selected to generate an electric field of approximately 1500 Volts per centimeter.
 9. The device of claim 1, wherein the body further comprises a base structured to stabilize the body relative to the tissue treatment region, and wherein the first and second passages are offset from the base.
 10. The device of claim 1, further comprising a handle extending from the body.
 11. The device of claim 1, wherein the body comprises a radiopaque material.
 12. The device of claim 1, wherein the first and second passages comprise an inner surface having a longitudinal track, and wherein each longitudinal track comprises a radiopaque material.
 13. The device of claim 1, wherein the body comprises a grip having a plurality of ribs.
 14. The device of claim 13, wherein the body comprises a plurality of vents, and wherein each vent is positioned between two adjacent ribs.
 15. The device of claim 1, wherein the body comprises an outer surface, and wherein the first passage comprises an outlet that opens the first passage to the outer surface.
 16. The device of claim 1, wherein the body comprises an elastomeric material, and wherein at least a portion of the body is moveable between a first configuration and a second configuration.
 17. The device of claim 16, wherein the body comprises an outer surface, and wherein the first passage comprises an outlet that operably closes the first passage to the outer surface when the body is in the first configuration.
 18. The device of claim 17, wherein the outlet operably opens the first passage to the outer surface when the body is moved to the second configuration such that the outlet permits passage of the first electrode therethrough.
 19. The device of claim 17, wherein the body generates a restoring force when moved from the first configuration to the second configuration such that the body seeks to return to the first configuration.
 20. The device of claim 1, further comprising: a third passage through the body, wherein the third passage is structured to axially restrain a third electrode; and a fourth passage through the body, wherein the fourth passage is structured to axially restrain a fourth electrode; wherein the third and fourth passages are substantially parallel to the first and second passages. 21-86. (canceled) 